JP4771736B2 - Torque sensor - Google Patents

Description

  The present invention relates to a torque sensor used, for example, to detect a steering torque of an automobile.

  As a conventional torque sensor, for example, a torque sensor disclosed in Japanese Patent Application Laid-Open No. 2002-310819 is known. This torque sensor has two rings facing in the axial direction, and is configured such that irregularities are formed on the opposed peripheral surfaces of these two rings, and these irregularities face each other. A magnetic circuit is formed between the rings, and a magnetic sensor for detecting a magnetic flux passing through the magnetic circuit is disposed.

  When the two rings rotate relative to each other according to the magnitude of the torsional torque applied, the opposing state of the concavo-convex surfaces of each ring changes, the magnetic resistance between them changes, and the output of the magnetic sensor changes. Therefore, the magnitude of the applied torque can be detected from the output of the magnetic sensor. However, since this conventional torque sensor always has a constant direction of the magnetic flux passing through the magnetic sensor, the magnetic sensor output is a unipolar type whose polarity is always constant and the magnitude of which is proportional to the torque. Even in the absence, the sensor output has a predetermined magnitude with a predetermined polarity, which is troublesome to handle. Therefore, a torque sensor that can obtain a bipolar-type output signal that can make the sensor output zero while no torque is applied is desired.

A torque sensor capable of obtaining this bipolar type output signal is disclosed in, for example, Japanese Patent Application Laid-Open No. 2-93321.
JP 2002-310819 A Japanese Patent Laid-Open No. 2-93321

  However, in the conventional torque sensor capable of obtaining a bipolar type output, the magnetic field generating means is formed by alternately forming N poles and S poles along the peripheral surface. In the conventional magnet structure in which the poles are alternately arranged on the peripheral surface, due to the variation in the magnetization of the N pole and the S pole, the boundary between the N pole and the S pole shifts, so that the torque does not work. The output signal of bipolar type does not become zero at the origin corresponding to the boundary between N pole and S pole, and the zero point of the output signal deviates from the origin, and the stable zero point of the output signal of the magnetic sensor at the origin It is difficult to obtain a signal value.

  The present invention proposes an improved torque sensor capable of obtaining a bipolar type output signal with improved zero point drift when no torque is applied.

In the torque sensor according to the present invention, a first rotating shaft and a second rotating shaft are disposed on a common axis, and the first rotating shaft and the second rotating shaft are coupled by a torsion bar, and the first rotating shaft and the second rotating shaft are coupled. A torque sensor for detecting a torsional torque applied between the rotating shaft and an inner peripheral rotating body connected to the first rotating shaft; an outer peripheral rotating body connected to the second rotating shaft and surrounding the inner rotating body; A magnetic field generating means disposed between the inner peripheral rotating body and the outer peripheral rotating body; a magnetic sensor through which the detected magnetic flux flows from the magnetic field generating means via the inner peripheral rotating body and the outer peripheral rotating body; and a first in a positive torque range. First magnetic field changing means for causing a detected magnetic flux to flow through the magnetic sensor in a predetermined direction in accordance with relative rotation between the rotating shaft and the second rotating shaft and changing the magnitude thereof, and the first rotating shaft and the second rotating in a negative torque range. The detected magnetic flux is applied to the magnetic sensor according to the relative rotation with the shaft. Second magnetic field changing means for changing the magnitude of the magnetic flux flowing in a direction opposite to the constant direction, the magnetic sensor having a polarity that changes in accordance with the direction of the detected magnetic flux, and a magnitude in accordance with the magnitude of the detected magnetic flux. The magnetic field generating means includes at least one enclosing magnet structure configured to generate a varying output signal and arranged to surround the common axis, the enclosing magnet structure having an outer circumferential magnetic pole surface about the common axis The surrounding magnet structure is composed of ring-shaped permanent magnets arranged around the common axis, and the outer magnetic pole surface has N and S poles along the common axis. only one magnetic pole of polarity in the magnetic poles are formed continuously in the inner circumferential magnetic pole surface also along the circumference of the common axis, only the other magnetic pole of polarity in the magnetic poles are continuously It is formed .

In another torque sensor according to the present invention, a first rotating shaft and a second rotating shaft are disposed on a common axis, and the first rotating shaft and the second rotating shaft are coupled by a torsion bar to perform the first rotation. A torque sensor for detecting a torsional torque applied between a shaft and a second rotating shaft, and an inner peripheral rotating body connected to the first rotating shaft and an inner peripheral rotating body connected to the second rotating shaft An outer periphery rotator, a magnetic field generating means disposed between the inner periphery rotator and the outer periphery rotator, a magnetic sensor through which the detected magnetic flux flows from the magnetic field generating means through the inner periphery rotator and the outer periphery rotator, and a positive torque First magnetic field changing means for causing a detected magnetic flux to flow in a predetermined direction through the magnetic sensor in accordance with the relative rotation between the first rotating shaft and the second rotating shaft in a range, and changing the magnitude of the detected magnetic flux, and a first rotation in a negative torque range. Magnetic flux detected according to relative rotation between the shaft and the second rotation shaft A second magnetic field changing means for causing the magnetic sensor to flow in a direction opposite to a predetermined direction and changing the magnitude of the magnetic sensor, the polarity of the magnetic sensor changing according to the direction of the detected magnetic flux, and the magnitude of the detected magnetic flux Wherein the magnetic field generating means includes at least one enclosing magnet structure arranged to surround the common axis, the enclosing magnet structure being arranged around the common axis. The surrounding magnet structure is composed of a ring-shaped magnet body arranged around a common axis, and the ring-shaped magnet body has both poles on the outer magnetic pole surface. Only the magnetic poles with one polarity are arranged at a predetermined angular interval around the common axis, and only the magnetic poles with the other polarity of the two magnetic poles are arranged along the common axis. Magnetized to line up at a predetermined angular interval It is characterized in.

  In the torque sensor according to the present invention, a magnetic field generating means disposed between the inner peripheral rotating body and the outer peripheral rotating body, and a detection magnetic path through which the detected magnetic flux flows from the magnetic field generating means through the inner peripheral rotating body and the outer peripheral rotating body, First magnetic field changing means for causing the detected magnetic flux to flow in a predetermined direction in accordance with the relative rotation between the first rotating shaft and the second rotating shaft in the positive torque range and changing the magnitude thereof, and the first rotation in the negative torque range. A second magnetic field changing means for changing the magnitude of the second magnetic field by flowing in a direction opposite to a predetermined direction according to the relative rotation of the shaft and the second rotating shaft, and the polarity of the second magnetic field changing means according to the direction of the detected magnetic flux. In addition, since a magnetic sensor that generates an output signal whose magnitude changes according to the magnitude of the detected magnetic flux is provided, a bipolar output signal that becomes zero when no torque is applied can be obtained.

In addition, in the torque sensor according to the present invention, in the positive torque range, the detected magnetic flux is passed through the magnetic sensor in a predetermined direction in accordance with the relative rotation between the first rotating shaft and the second rotating shaft, and the magnitude of the first magnetic field is changed. Changing means and second magnetic field changing means for causing the detected magnetic flux to flow through the magnetic sensor in a direction opposite to a predetermined direction in accordance with relative rotation between the first rotating shaft and the second rotating shaft in a negative torque range, and changing the magnitude thereof. , Composed of ring-shaped permanent magnets arranged around the common axis, and only one of the N and S poles on the outer peripheral magnetic pole surface along the common axis. are formed continuously, and the inner peripheral magnetic pole surface thereof, along the circumference of the common axis, surrounds the magnet configuration only the other magnetic pole of polarity in the magnetic poles are formed continuously or about a common axis, It consists of a ring-shaped magnet body arranged in On the outer peripheral magnetic pole surface, only one polarity magnetic pole of both magnetic poles is arranged at a predetermined angular interval around the common axis, and the inner peripheral magnetic pole surface has the other polarity of both magnetic poles. Only magnetic poles are combined with magnetic field generating means having a surrounding magnet structure magnetized so as to be arranged at a predetermined angular interval around the common axis . The enclosed magnet structure thus magnetized does not have N poles and S poles arranged alternately along the peripheral surface unlike the conventional magnet structure, and has the same polarity on the outer peripheral magnetic pole surface and the inner peripheral magnetic pole surface. Since the magnetic poles are arranged, the boundary between the N pole and the S pole on the same peripheral surface does not shift as in the conventional magnet structure. Therefore, it is possible to improve the deviation of the zero point of the bipolar type output signal from the origin, and a stable zero point output can be obtained.

  Hereinafter, several embodiments of a torque sensor according to the present invention will be described with reference to the drawings.

Embodiment 1.
1, 2 and 3 are views showing the torque sensor according to the first embodiment of the present invention at its origin position. 4, FIG. 5 and FIG. 6 are views showing the torque sensor according to the first embodiment of the present invention in the positive torque range. FIGS. 1 and 4 are top views of the torque sensor according to the first embodiment when viewed in the axial direction, but some of the components are omitted to make the drawings easier to see. 2 and 5 are longitudinal sectional views of the torque sensor according to the first embodiment cut along a plane including the common axis LL. FIGS. 3 and 6 are diagrams for explaining the operation of the torque sensor according to the first embodiment. FIG. 3 shows the flow of magnetic flux at the origin position, and FIG. 6 shows the flow of magnetic flux in the positive torque range. 7 is a cross-sectional view taken along line AA in FIG. 5, FIG. 8 is a cross-sectional view taken along line BB in FIG. 5, FIG. 9 is a cross-sectional view taken along line CC in FIG. FIG. The AA line, the BB line, the CC line, and the DD line are all included in a plane orthogonal to the common axis line LL. FIG. 11 is a side view of the torque sensor according to the first embodiment.

  With reference to these FIGS. 1-11, the torque sensor of Embodiment 1 by this invention is demonstrated. First, the torque sensor according to the first embodiment of the present invention includes a first rotating shaft 1, a second rotating shaft 2, an inner peripheral rotating body 3, a base plate 4 and the like as shown in FIGS. A torsion bar 5, a magnetic field generating means 6, an outer peripheral rotating body 12, a magnetic field changing means 30, and a magnetic sensor 15 are provided.

  The torque sensor according to the first embodiment is a sensor that detects torsional torque that acts between the first rotating shaft 1 and the second rotating shaft 2, and in electric power steering that is mounted on an automobile, torque that acts on the steering wheel. Used to detect. The first and second rotating shafts 1 and 2 are rotatably arranged on a common axis LL that is common to each other. Between the first and second rotating shafts 1 and 2, an inner peripheral rotating body 3, a base plate 4, a torsion bar 5, a magnetic field generating means 6, an outer peripheral rotating body 12, and a magnetic field changing means 30 are arranged. The inner peripheral rotating body 3 is an inner peripheral cylinder centered on the common axis LL and is made of a magnetic material such as an iron material. One end of the inner peripheral cylinder 3 is coupled to the first rotary shaft 1 and rotates around the common axis LL together with the first rotary shaft 1.

  The base plate 4 is a disc coupled to one end of the second rotating shaft 2 and rotates around the common axis LL together with the second rotating shaft 2. The torsion bar 5 is disposed inside the inner peripheral cylinder 3 and extends along the common axis LL. One end of the torsion bar 5 is coupled to the inner peripheral cylinder 3, and the other end is coupled to the center portion of the base plate 4. As a result, the torsion bar 5 connects the inner peripheral cylinder 3 and the base plate 4. Since the torsional rigidity of the inner cylinder 3 is sufficiently larger than the torsional rigidity of the torsion bar 5, if a torsional torque is applied between the first rotating shaft 1 and the second rotating shaft 2, the torsional rigidity depends on the magnitude of the torque. The torsion bar 5 is twisted around the common axis LL, and the first rotary shaft 1 and the second rotary shaft 2 rotate relatively around the common axis LL.

  The outer peripheral rotating body 12 is a cylindrical body arranged so as to surround the inner peripheral cylinder 3. The outer peripheral rotating body 12 is arranged around the common axis LL, one end is coupled to the base plate 4, and rotates around the common axis LL together with the base plate 4. As shown in FIG. 11, the outer peripheral rotating body 12 includes a first outer peripheral cylinder 12 a, a second outer peripheral cylinder 12 b, and a connecting body 13. The first and second outer peripheral cylinders 12 a and 12 b are arranged side by side along the common axis LL and are connected to each other by the connecting body 13. The outer cylinders 12a and 12b are made of a magnetic material such as iron, and the coupling body 13 is made of a nonmagnetic material such as aluminum.

As shown in FIG. 11, the connecting body 13 is formed in a substantially cylindrical shape, and has a hollow portion in a part of the cylindrical shape, in which the protruding portions 12 c and 12 d of the outer peripheral cylinders 12 a and 12 b are connected to a common axis L. The magnetic sensor 15 is disposed between the projecting portions 12c and 12d, facing the -L direction. The protrusions 12c and 12d of the outer cylinders 12a and 12b constitute a detection magnetic path 20 extending along the common axis LL between the outer cylinders 12a and 12b, and the detection magnetic path DF has a detection magnetic flux DF. Flowing. The magnetic sensor 15 is disposed between the projecting portions 12c and 12d so as to cross the detection magnetic path 20, and a detection magnetic flux DF is applied to the magnetic sensor 15. In the first embodiment, the magnetic sensor 15 is installed so as to rotate together with the outer peripheral rotating body 12. The detected magnetic flux DF includes a detected magnetic flux DF1 from the first outer peripheral cylinder 12a toward the second outer peripheral cylinder 12b and a detected magnetic flux DF2 from the second outer peripheral cylinder 12b toward the first outer peripheral cylinder 12a. In FIG. 11, the detected magnetic flux DF1 is indicated by a solid line, and the detected magnetic flux DF2 is indicated by a dotted line.

  As shown in FIGS. 2 and 5, four stages A, B, C, and D are set between the inner peripheral rotator 3 and the outer peripheral rotator 12 along the common axis LL. The stages A, B, C, and D are respectively set on the planes including the AA, BB, CC, and DD lines that are orthogonal to the common axis LL. These four stages A, B, C, and D are set apart from each other along the common axis LL.

  The magnetic field generating means 6 is arranged on the stages B and C among these stages A, B, C and D. Further, the magnetic field changing means 30 is arranged on all of the stages A, B, C, and D. First, the magnetic field generating means 6 has two surrounding magnet structures 6B and 6C in the first embodiment, and these surrounding magnet structures 6B and 6C are arranged on the stages B and C, respectively. The enclosing magnet structure 6B arranged on the stage B and the enclosing magnet structure 6C arranged on the stage C are configured by ring-shaped permanent magnets 62 and 63, respectively.

  The surrounding magnet structure 6B is disposed so as to surround the common axis LL, and has an inner peripheral magnetic pole surface 62a and an outer peripheral magnetic pole surface 62b centered on the common axis LL. The inner peripheral magnetic pole surface 62a and the outer peripheral magnetic pole surface 62b are formed on the inner peripheral surface and the outer peripheral surface of the ring-shaped permanent magnet 62, respectively. Similarly, the surrounding magnet structure 6C is also arranged so as to surround the common axis LL, and has an inner peripheral magnetic pole surface 63a and an outer peripheral magnetic pole surface 63b centered on the common axis LL. The inner peripheral magnetic pole surface 63a and the outer peripheral magnetic pole surface 63b are formed on the inner peripheral surface and the outer peripheral surface of the ring-shaped permanent magnet 63, respectively. These ring-shaped permanent magnets 62 and 63 have their inner peripheral magnetic pole surfaces 62 a and 63 a fitted into the outer peripheral surface of the inner peripheral tube 3 and fixed to the inner peripheral tube 3, and rotate together with the inner peripheral tube 3.

  The ring-shaped permanent magnets 62 and 63 are each magnetized in the radial direction centered on the common axis LL, and the respective inner peripheral magnetic pole surfaces 62a and 63a are around the common axis LL. The outer peripheral magnetic pole surfaces 62b and 63b are, for example, N poles along the common axis L-L. It has become. In other words, on the inner peripheral magnetic pole surfaces 62a and 63a of the ring-shaped permanent magnets 62 and 63, only the S pole, which is one of the N and S poles, continues along these peripheral surfaces. Similarly, on the outer peripheral magnetic pole surfaces 62b and 63b of the ring-shaped permanent magnets 62 and 63, only the N poles in both magnetic poles are continuously formed along the peripheral surfaces.

  In the first embodiment, only the S pole is formed on the inner peripheral magnetic pole surfaces 62a and 63a of the ring-shaped permanent magnets 62 and 63, and only the N pole is formed on the outer peripheral magnetic pole surfaces 62b and 63b. This is effective in suppressing variations in magnetization in the magnetic field generating means 6. For example, not only S poles but also S poles and N poles are alternately formed on the inner peripheral magnetic pole surfaces 62a and 63a, and N poles and S poles are alternately formed on the outer peripheral magnetic pole surfaces 62b and 63b. In the formed structure, the N pole and the S pole are magnetized so as to be adjacent to each other, and it is difficult to eliminate variations in the magnetization. Compared to this, as in the first embodiment, for example, only S poles are provided on the inner peripheral magnetic pole surfaces 62a, 63a of the ring-shaped permanent magnets 62, 63, and only N poles are provided on the outer peripheral magnetic pole surfaces 62b, 63b. The configuration in which is formed can eliminate the disadvantage that the boundary between the N pole and the S pole on the same peripheral surface is shifted due to variation in magnetization, as in the conventional magnet structure.

  When the entire ring-shaped permanent magnets 62 and 63 are magnetized in the radial direction of the common axis LL, the magnetization direction is reversed to the above, and the inner peripheral magnetic pole surfaces 62a and 63a are arranged on the peripheral surfaces. It is also possible to continuously form only the N pole along the circumference and continuously form only the S pole along the peripheral surfaces of the outer peripheral magnetic pole faces 62b and 63b. In this case as well, variation in magnetization can be suppressed as described above.

  The magnetic field changing means 30 includes four magnetic field changing means 31 to 34. These four magnetic field changing units 31 to 34 are arranged on the stages A to D between the inner peripheral rotating body 3 and the outer peripheral rotating body 12, respectively. These four magnetic field changing means 31, 32, 33, 34 are each constituted by a plurality of protruding magnetic poles arranged around the common axis LL.

  The magnetic field changing means 31 arranged on the stage A is composed of an inner peripheral magnetic pole 11a and an outer peripheral magnetic pole 14a. Both the inner peripheral magnetic pole 11a and the outer peripheral magnetic pole 14a have a plurality of protruding magnetic poles around the common axis LL. The inner peripheral magnetic pole 11a and the outer peripheral magnetic pole 14a are opposed to each other with a gap in the radial direction centered on the common axis LL. The inner peripheral magnetic pole 11 a is disposed on the outer peripheral surface of the ring-shaped iron core 9 fixed to the outer peripheral surface of the inner peripheral cylinder 3. The outer peripheral magnetic pole 14a is disposed on the inner peripheral surface of the first outer peripheral cylinder 12a. In the stage A, these magnetic poles 11a and 14a change their facing state according to the relative rotation between the inner peripheral rotating body 3 and the outer peripheral rotating body 12, and change the magnetic flux passing through the gap between them.

  The magnetic field changing means 32 disposed on the stage B includes an inner peripheral magnetic pole 11b and an outer peripheral magnetic pole 14b. Both the inner peripheral magnetic pole 11b and the outer peripheral magnetic pole 14a have a plurality of protruding magnetic poles around the common axis LL. The inner peripheral magnetic pole 11b and the outer peripheral magnetic pole 14b are opposed to each other via a gap in the radial direction centered on the common axis LL. The inner peripheral magnetic pole 11b is disposed on the outer peripheral magnetic pole surface 62b of the ring-shaped permanent magnet 62 constituting the surrounding magnet structure 6B. The outer peripheral magnetic pole 14b is disposed on the inner peripheral surface of the first outer peripheral cylinder 12a. In the stage B, these magnetic poles 11b and 14b change their opposing states according to the relative rotation between the inner peripheral rotating body 3 and the outer peripheral rotating body 12, and change the magnetic flux passing through the gap between them.

  As shown in FIG. 3, the ring-shaped permanent magnet 62 constituting the enclosing magnet structure 6B of the magnetic field generating means 6 has an inner magnetic pole 11b and an outer magnetic pole 14b of the magnetic field changing means 32 from the outer magnetic pole face 62b which is an N pole. The magnetic flux Φ1 passes through the first outer circumferential cylinder 12a, the outer circumferential magnetic pole 14a and the inner circumferential magnetic pole 11a of the magnetic field changing means 31, the ring-shaped iron core 9, and the inner circumferential cylinder 3, and returns to the inner circumferential magnetic pole face 62a that is the S pole. Shed. The inner peripheral magnetic pole 11b and the outer peripheral magnetic pole 14b of the magnetic field changing means 32 and the inner peripheral magnetic pole 11a and the outer peripheral magnetic pole 14a of the magnetic field changing means 31 change the magnitude of the magnetic flux Φ1 based on the change in the opposing state.

  The magnetic field changing means 33 arranged on the stage C includes an inner peripheral magnetic pole 11c and an outer peripheral magnetic pole 14c. Both the inner peripheral magnetic pole 11c and the outer peripheral magnetic pole 14c have a plurality of protruding magnetic poles around the common axis LL. The inner peripheral magnetic pole 11c and the outer peripheral magnetic pole 14c are opposed to each other via a gap in the radial direction centered on the common axis LL. The inner peripheral magnetic pole 11c is disposed on the outer peripheral magnetic pole surface 63b of the ring-shaped permanent magnet 63 constituting the surrounding magnet structure 6C. The outer peripheral magnetic pole 14c is disposed on the inner periphery of the second outer peripheral cylinder 12b. In the stage C, these magnetic poles 11c and 14c change their opposing states according to the relative rotation between the inner peripheral rotator 3 and the outer peripheral rotator 12, and change the magnetic flux passing through the gap between them.

  The magnetic field changing means 34 disposed on the stage D includes an inner peripheral magnetic pole 11d and an outer peripheral magnetic pole 14d. Both the inner peripheral magnetic pole 11d and the outer peripheral magnetic pole 14d have a plurality of protruding magnetic poles around the common axis LL. The inner circumferential magnetic pole 11d and the outer circumferential magnetic pole 14d are opposed to each other via a gap in the radial direction centered on the common axis LL. The inner peripheral magnetic pole 11 d is disposed on the outer peripheral surface of the ring-shaped iron core 10 fixed to the outer peripheral surface of the inner peripheral cylinder 3. The outer peripheral magnetic pole 14d is disposed on the inner peripheral surface of the second outer peripheral cylinder 12b. In the stage D, these magnetic poles 11a and 14a change their facing state according to the relative rotation between the inner peripheral rotating body 3 and the outer peripheral rotating body 12, and change the magnetic flux passing through the gap between them.

Note that the lengths of the inner peripheral magnetic poles 11a, 11b, 11c, and 11d in the common axis LL direction are all the same, and the outer peripheral magnetic poles 14a, 14b, 14c, and 14d are also longer in the common axis LL direction. All are the same. In addition, the radial lengths of the gaps between the inner peripheral magnetic poles 11a , 11b , 11c , 11d and the outer peripheral magnetic poles 14a, 14b, 14c, 14d in the stages A, B, C, D are all the same. Is done.

  As shown in FIG. 3, the ring-shaped permanent magnet 63 constituting the enclosing magnet structure 6C of the magnetic field generating means 6 has an inner peripheral magnetic pole 11c and an outer peripheral magnetic pole 14c of the magnetic field changing means 33 from the outer peripheral magnetic pole face 63b which is an N pole. The magnetic flux Φ2 passes through the second outer peripheral cylinder 12b, the outer peripheral magnetic pole 14d and the inner peripheral magnetic pole 11d of the magnetic field changing means 34, the ring-shaped iron core 10, and the inner peripheral cylinder 3, and returns to the inner peripheral magnetic pole face 63a that is the S pole. Shed. The inner peripheral magnetic pole 11c and the outer peripheral magnetic pole 14c of the magnetic field changing means 33, and the inner peripheral magnetic pole 11d and the outer peripheral magnetic pole 14d of the magnetic field changing means 34 change the magnitude of the magnetic flux Φ2 based on the change in the opposing state.

  The inner peripheral magnetic poles 11a and 11b of the magnetic field changing means 31 and 32 arranged in the stages A and B and the inner peripheral magnetic poles 11c and 11d of the magnetic field changing means 33 and 34 arranged in the stages C and D are the common axis L−. A plurality of protruding magnetic poles arranged around L with the same phase as each other. Specifically, each of these inner peripheral magnetic poles 11a to 11d has nine protruding magnetic poles arranged at an angular interval of 40 degrees, but for each of the inner peripheral magnetic poles 11a to 11d, these nine The protruding magnetic poles are positioned at angular positions of, for example, 0 degree, 40 degrees, 80 degrees, 120 degrees, 160 degrees, 200 degrees, 240 degrees, 280 degrees, and 320 degrees from the inner circumferential magnetic pole reference position around the common axis LL. Are arranged in the same phase. In FIG. 1 and FIG. 4, the salient poles of these inner peripheral magnetic poles 11a to 11d are shown by solid lines in a state where they all overlap each other in the direction of the common axis LL.

In Stage A, B, C, the outer peripheral magnetic pole 14a~14d of the magnetic field changing means 31 to 34 are arranged in D, a periphery magnetic poles 14b of the field changing means 32, the outer peripheral magnetic pole 14d of magnetic field varying means 34, the common axis A plurality of magnetic poles arranged in the same phase around LL. Specifically, the outer peripheral magnetic poles 14b and 14d each have nine protruding magnetic poles arranged at an angular interval of 40 degrees, but for the outer peripheral magnetic poles 14b and 14d, these nine protruding magnetic poles have a common axis. Arranged in the same phase at angular positions of 0 degree, 40 degrees, 80 degrees, 120 degrees, 160 degrees, 200 degrees, 240 degrees, 280 degrees, and 320 degrees from the outer peripheral magnetic pole reference position around LL. . In FIG. 1 and FIG. 4, the projecting magnetic poles of these outer peripheral magnetic poles 14b and 14d are shown by solid lines in a state where they all overlap each other in the direction of the common axis LL. For one of these outer peripheral magnetic pole 1 4 overlapping each other b, 1 4 d, 1 the angular position of its center, in FIG. 4 are indicated by .theta.1.

Of the outer peripheral magnetic poles 14a to 14d of the magnetic field changing means 31 to 34, the outer peripheral magnetic pole 14a of the magnetic field changing means 31 and the outer peripheral magnetic pole 14c of the magnetic field changing means 33 are arranged in the same phase around the common axis LL. It has a plurality of magnetic poles. Specifically, each of the outer peripheral magnetic poles 14a and 14c has nine protruding magnetic poles arranged at an angular interval of 40 degrees, but for the magnetic pole 14a and the magnetic pole 14c, these nine protruding magnetic poles have a common axis. from the outer peripheral magnetic pole reference positions around the L-L, magnetic pole 1 4b, 1 4 d exactly opposite phase, 20 degrees, 60 degrees, 100 degrees, 140 degrees, 180 degrees, 220 degrees, 260 degrees, 300 degrees, They are arranged in the same phase at 340 degree angular positions. In FIG. 1 and FIG. 4, the protruding magnetic poles of these outer peripheral magnetic poles 14a and 14c are indicated by dotted lines in a state where they all overlap each other in the direction of the common axis LL. For one of the outer overlapping these mutual circumferential magnetic pole 1 4a, 1 4c, FIG. 1 the angular position of its center, in FIG. 4 are indicated by .theta.2.

  The magnetic sensor 15 is, for example, a Hall element, and generates an output signal corresponding to the direction and magnitude of the detected magnetic flux DF passing therethrough. In the magnetic sensor 15, detection magnetic fluxes DF1 and DF2 flowing along the common axis LL flow between the first outer peripheral cylinder 12a and the second outer peripheral cylinder 12b. The polarity of the output signal of the magnetic sensor 15 is an output signal in which the polarity of the positive polarity and that of the negative polarity are reversed according to the direction of the detected magnetic fluxes DF1 and DF2 passing through the magnetic sensor 15, and the magnitude of this output signal is It is proportional to the magnitude of the detected magnetic fluxes DF1 and DF2 passing through the sensor 15.

  In FIGS. 1 and 4, the first and second rotating shafts 1 and 2, the inner peripheral cylinder 3, the torsion bar 5, and the ring-shaped iron core 9 are omitted in order to make the drawings easy to see.

  1 to 3 show the torque sensor of the first embodiment at its origin position. At this origin position, in the magnetic field changing means 31-34, the inner peripheral magnetic poles 11a, 11b, 11c, 11d are outer peripheries indicated by solid lines along the circumferential direction around the common axis LL as shown in FIG. It is located at an intermediate angular position between the angular position θ1 where the magnetic poles 14b and 14d overlap and the angular position θ2 where the magnetic poles 14a and 14c overlap as shown by dotted lines.

  At this origin position, the magnetic flux Φ1 and the magnetic flux Φ2 shown in FIG. At this origin position, the inner peripheral magnetic poles 11a, 11b, 11c, 11d of the magnetic field changing means 31-34 are arranged along the circumferential direction around the common axis LL as shown in FIG. It is located at an intermediate angular position between the overlapping angular position θ1 and the overlapping angular position θ2 of the magnetic poles 14a, 14c. Therefore, the magnetic resistances of the magnetic paths through which the magnetic fluxes Φ1 and Φ2 shown in FIG. 3 flow are equal to each other, and therefore the magnitudes of the magnetic fluxes Φ1 and Φ2 are equal to each other. Therefore, the detected magnetic fluxes DF1 and DF2 flowing through the magnetic sensor 15 between the first outer peripheral cylinder 12a and the second outer peripheral cylinder 12b are both zero, and the signal output of the magnetic sensor 15 is also zero.

  4, 5, and 6, the first rotating shaft 1 rotates counterclockwise relative to the second rotating shaft 2 from the origin position, and the magnetic poles 11 a, 11 b, 11 c, and 11 d are connected to the magnetic pole 14 b, A positive torque range displaced to a rotation angle close to the overlapping angular position θ1 of 14d is shown. In this positive torque range, the magnetic poles 11a, 11b, 11c, and 11d are away from the angular position θ2 where the magnetic poles 14a and 14c overlap and are close to the angular position θ1 where the magnetic poles 14b and 14d overlap.

7 to 10 are cross-sectional view in a direction perpendicular to the common axis L-L in stages A, B, C, D shown in FIG. 5, respectively. In the magnetic field changing means 31 of the stage A shown in FIG. 7, the nine protruding magnetic poles of the inner peripheral magnetic pole 11a are away from the angular position θ2 and approach the angular position θ1 with respect to the nine protruding magnetic poles of the outer peripheral magnetic pole 14a. Yes. Similarly, in the magnetic field changing means 33 shown in the stage C shown in FIG. 9, the nine protruding magnetic poles of the inner peripheral magnetic pole 11c are moved away from the angular position θ2 with respect to the nine protruding magnetic poles of the outer peripheral magnetic pole 14c. It is approaching θ1. Therefore, the facing area between the inner peripheral magnetic poles 11a, 11c and the outer peripheral magnetic poles 14a, 14c of the magnetic field changing means 31, 33 is reduced, and the magnetic resistance is larger than the magnetic resistance at the origin position shown in FIGS. It is increasing.

On the other hand, in the magnetic field changing means 32 of the stage B shown in FIG. 8, the nine protruding magnetic poles of the inner peripheral magnetic pole 11b are also moved away from the angular position θ2 to the angular position θ1 with respect to the nine protruding magnetic poles of the outer peripheral magnetic pole 14b. Approaching and approaching the outer peripheral magnetic pole 14b. Similarly, in the magnetic field changing means 34 shown in the stage D shown in FIG. 10, the nine protruding magnetic poles of the inner peripheral magnetic pole 11d are also moved away from the angular position θ2 with respect to the nine protruding magnetic poles of the outer peripheral magnetic pole 14d. It approaches θ1 and approaches the outer peripheral magnetic pole 14d. Therefore, the inner peripheral magnetic pole 11b of the magnetic field change means 32 and 34, increases opposing area between 11d and the outer magnetic pole 14b, 1 4 d, magnetoresistance, magnetic resistance at the origin position shown in FIGS. 1 to 3 Is less than.

  In the positive torque range shown in FIGS. 4 to 10, since the opposing areas of the inner peripheral magnetic poles 11b and 11d and the outer peripheral magnetic poles 14b and 14d of the magnetic field changing means 32 and the magnetic field changing means 34 are both increased, FIG. As shown, the detection magnetic flux DF1 newly flows from the first outer peripheral cylinder 12a toward the second outer peripheral cylinder 12b. The detected magnetic flux DF1 passes from the outer peripheral magnetic pole surface 62b of the enclosing magnet structure 6B in the stage B to the first outer peripheral cylinder 12a through the magnetic poles 11b and 14b of the magnetic field changing means 32, and from the first outer peripheral cylinder 12a to the common axis LL. Along the magnetic sensor 15 in the detection magnetic path 20, to the second outer peripheral cylinder 12 b, and to the inner peripheral cylinder 3 through the ring-shaped iron core 10.

  The magnetic sensor 15 detects the detection magnetic flux DF1 flowing through the detection magnetic path 20, and generates, for example, a positive signal output. This positive signal output is obtained in the positive torque range, that is, in the range in which the detection magnetic flux DF1 passing through the magnetic field changing means 32, 34 is generated from the surrounding magnet structure 6B, and the magnitude of the output signal is in this positive torque range. , The torque increases with an increase in torsional torque applied between the first and second rotating shafts 1 and 2. In the positive torque range, since the opposing areas of the magnetic poles 11a and 14a of the magnetic field changing means 31 and the magnetic poles 11c and 14c of the magnetic field changing means 33 are reduced, the magnetic flux Φ1 passing through these magnetic field changing means 31 and 33, The size of Φ2 decreases.

From the origin position shown in FIG. 3, the first rotating shaft 1 rotates relative to the second rotating shaft 2 in the clockwise direction, opposite to the positive torque range shown in FIGS. peripheral magnetic pole 11a, 11b, 11c, 11d is, in the negative torque range displaced to an angle position close to the magnetic pole 14 a, angular position θ2 of overlapping 14c, torsional torque applied between the first and second rotary shafts 1 and 2 However, the reverse direction is obtained with respect to the positive torque range. In this negative torque range, the magnetic poles 11a, 11b, 11c, and 11d move away from the angular position θ1 where the magnetic poles 14b and 14d overlap, and the angular position θ2 where the magnetic poles 14a and 14c overlap, rather than the origin position shown in FIGS. It is in a state approaching.

  In this negative torque range, since the opposing areas of the magnetic poles 11a and 14a of the magnetic field changing means 31 and the magnetic poles 11c and 14c of the magnetic field changing means 33 increase, the magnetic field changes from the surrounding magnet structure 6C in the stage C. The detected magnetic flux DF2 passing through the means 31 and 33 is generated, and conversely, the opposing area of the magnetic poles 11b and 14b of the magnetic field changing means 32 and the magnetic poles 11d and 14d of the magnetic field changing means 34 is reduced. , 34, the magnitudes of the magnetic fluxes Φ1, Φ2 are reduced.

  The detected magnetic flux DF2 in this negative torque range passes from the surrounding magnet structure 6C in the stage C to the second outer peripheral cylinder 12b through the magnetic poles 11c and 14c of the magnetic field changing means 33, and from the second outer peripheral cylinder 12b to the common axis LL. , Passes through the magnetic sensor 15 in the detection magnetic path 20, reaches the first outer cylinder 12 a, and returns to the inner cylinder 3 via the ring-shaped iron core 9. The magnetic sensor 15 detects the detected magnetic flux DF2 and generates, for example, a negative signal output. This negative signal output is obtained in the negative torque range, that is, the range in which the magnetic flux passing through the magnetic field changing means 31 and 33 increases and the magnetic flux passing through the magnetic field changing means 32 and 34 decreases, and the magnitude of the output signal In this negative torque range, increases in response to a decrease in reverse torsional torque applied between the first and second rotating shafts 1 and 2.

  In the torque sensor, a relative rotation of, for example, ± 10 degrees, in other words, 20 degrees occurs between the rotating shafts 1 and 2, and a change in torsional torque in that angular range, that is, a relative rotation between the rotating shafts 1 and 2 Is detected. When this 20-degree relative rotation range is called a detection range, in the first embodiment, the detection range corresponds to the origin position shown in FIG. 3 in the middle, and the output signal of the magnetic sensor 15 is in the negative torque range. The output signal of the magnetic sensor 15 is set so as to change substantially linearly from the first angular position at which the maximum negative polarity value is reached to the second angular position at which the maximum positive polarity value is reached in the positive torque range. In the first embodiment, the output signal becomes zero at the origin position just between the first angular position and the second angular position.

  Specifically, in the first embodiment, the angle between the angle positions θ1 and θ2 is 20 degrees, and the origin position is set just in the middle, so the detection range is from the origin position to the angle position θ2 side. It is set between the first angular position approaching 10 degrees and the second angular position approaching 10 degrees from the origin position to the angular position θ1 side. The first angular position is in a negative torque range, and the output signal of the magnetic sensor 15 has a negative maximum value at the first angular position. The second angular position is in the positive torque range, and the output signal of the magnetic sensor 15 has a maximum positive value at the second angular position.

  In this manner, in the first embodiment, an output signal whose polarity is reversed and whose magnitude increases almost linearly with the increase in the torsional torque to be applied in the detection range is obtained from the magnetic sensor 15, and as a result Thus, a torque sensor that generates a bipolar type output signal can be realized. The torque sensor that generates the bipolar type output signal has an origin position where the polarity of the output signal is inverted, and calibration of variations in the sensor output value at the origin position can be easily calibrated.

Further, in the torque sensor of the first embodiment, the magnetic field generating means 6 includes the surrounding magnet structures 6B and 6C arranged so as to surround the common axis LL, and the surrounding magnet structures 6B and 6C have the common axis L The outer peripheral magnetic pole surfaces 62b and 63b and the inner peripheral magnetic pole surfaces 62a and 63a centering on -L are formed, and the outer peripheral magnetic pole surfaces 62b and 63b have N and S poles around the common axis LL. Only one polarity magnetic pole of both magnetic poles is arranged, and only the magnetic pole of the other polarity of both magnetic poles is arranged on the inner peripheral magnetic pole surfaces 62a and 63a along the common axis LL. a manner, since it is magnetized in the radial direction around the common axis L-L, as in the conventional magnet structure, the zero point of the output signal due to variations in magnetization is the boundary of N and S poles Eliminates inconveniences that deviate from the corresponding origin, and stable zero point output It is possible to obtain.

  In the first embodiment, a solid shaft is used instead of the inner peripheral cylinder constituting the inner peripheral rotating body 3, and the torsion bar 5 may be installed at another position so as to connect the rotary shafts 1 and 2. it can. Further, as the material of the nonmagnetic coupling body 13, other nonmagnetic materials such as aluminum and a resin material may be used. In the first embodiment, nine protruding magnetic poles are formed on each of the inner peripheral magnetic poles 11a, 11b, 11c, 11d and the outer peripheral magnetic poles 14a, 14b, 14c, 14d. However, the number of the protruding magnetic poles is limited to nine. Of course, other numbers can be used. Further, instead of forming the projecting magnetic poles, the magnetic resistance may be changed by relative rotation, such as by providing a notch or a hole in the peripheral surface.

  In the first embodiment, the inner peripheral magnetic poles 11a, 11b, 11c, and 11d are all in phase, and the outer peripheral magnetic poles 14a, 14b, 14c, and 14d are the same in phase with the outer peripheral magnetic poles 14a and 14c and the outer peripheral magnetic poles 14b and 14d, respectively. In addition, the outer peripheral magnetic poles 14a and 14c and the outer peripheral magnetic poles 14b and 14d are reversed in phase, but these relations are reversed so that the outer peripheral magnetic poles 14a, 14b, 14c and 14d are all in phase, and the inner peripheral magnetic pole 11a, For 11b, 11c, and 11d, the inner peripheral magnetic poles 11a and 11c and the inner peripheral magnetic poles 11b and 11d are in phase, and the inner peripheral magnetic poles 11a and 11c and the inner peripheral magnetic poles 11b and 11d are out of phase. As in the first embodiment, a bipolar type output signal can be obtained from the magnetic sensor 15.

  In the first embodiment, the two surrounding magnet structures 6B and 6C are arranged on the stages B and C. However, a magnetic field is generated in each of the stages B and C by one surrounding magnet structure straddling the stages B and C. In addition, the magnetic fluxes Φ1 and Φ2 and the detection magnetic fluxes DF1 and DF2 may flow between the inner peripheral magnetic poles 11b and 11c and the outer peripheral magnetic poles 14b and 14c. In this case, one enclosing magnet structure is formed in a cylindrical shape along the common axis LL, and this is also magnetized in the radial direction centered on the common axis LL, as in the first embodiment. The inner peripheral magnetic pole surface is configured such that only one of the N and S poles is continuous, and the outer magnetic pole surface is continuous with only the other magnetic pole.

  In Embodiment 1, the surrounding magnet structures 6B and 6C are arranged on the stages B and C, respectively. However, these surrounding magnet structures 6B and 6C can be arranged on the stages A and D, respectively. Also in this case, the magnetic flux Φ1 and the detected magnetic flux DF1 are caused to flow by the enclosing magnet structure arranged on the stage A, and the magnetic flux Φ2 and the detected magnetic flux DF2 are made to flow by the enclosing magnet structure arranged on the stage D.

  Further, in the first embodiment, the inner circumferential magnetic poles 11a, 11b, 11c, 11d and the outer circumferential magnetic poles 14a, 14b, 14c, 14d are all assumed to have the same length in the common axis LL direction. For example, the length of the magnetic poles 11b, 11c, 14b, and 14c in the common axis LL direction in the stages B and C in which the surrounding magnet structures 6B and 6C are disposed is set to the magnetic poles 11a, 11d, 14a, and 14d in the stages A and D. The length in the direction of the common axis LL can be made longer.

Embodiment 2. FIG.
12 is a sectional view showing a torque sensor according to a second embodiment of the present invention. FIG. 12 is a longitudinal sectional view taken along a plane including the common axis LL, and is a sectional view corresponding to FIGS. 2 and 5.

  In the second embodiment, the magnetic field generating means 6 is arranged on all the stages A, B, C, and D. In the second embodiment, the magnetic field generating means 6 includes the surrounding magnet structures 6A and 6D arranged in the stages A and D in addition to the surrounding magnet structures 6B and 6C arranged in the stages B and C. The other configuration is the same as that of the first embodiment. In the second embodiment, the surrounding magnet structures 6A, 6B, 6C, and 6D constituting the magnetic field generating means 6 and the magnetic field changing means 31 to 34 are arranged in the stages A, B, C, and D, respectively.

  The surrounding magnet structure 6A disposed on the stage A is configured by a ring-shaped permanent magnet 61, and the surrounding magnet structure 6D disposed on the stage D is configured by a ring-shaped permanent magnet 64. The ring-shaped permanent magnets 61 and 64 are respectively arranged so as to surround the common axis LL, and have inner peripheral magnetic pole surfaces 61a and 64a and outer peripheral magnetic pole surfaces 61b and 64b with the common axis LL as the center. The ring-shaped permanent magnets 61 and 64 are fixed by fitting the inner peripheral magnetic pole surfaces 61 a and 64 a to the outer peripheral surface of the inner peripheral cylinder 3, and rotate together with the inner peripheral cylinder 3. The inner peripheral magnetic poles 11 a and 11 d of the magnetic field changing means 31 and 34 are arranged on the outer periphery of the permanent magnets 61 and 64.

  These ring-shaped permanent magnets 61 and 64 are magnetized in the radial direction centered on the common axis LL, but are magnetized with a polarity opposite to that of the ring-shaped permanent magnets 62 and 63. Specifically, the ring-shaped permanent magnet 61 is magnetized with a polarity opposite to that of the ring-shaped permanent magnet 62, and the inner peripheral magnetic pole surface 61a has an N pole continuously around the common axis LL. The outer peripheral magnetic pole surface 61b is magnetized so as to continuously form an S pole along the common axis LL. Similarly, the ring-shaped permanent magnet 64 is magnetized with a polarity opposite to that of the ring-shaped permanent magnet 63, and the inner peripheral magnetic pole surface 64a continuously forms an N pole around the common axis LL. The outer peripheral magnetic pole surface 64b is magnetized so as to continuously form an S pole along the common axis LL.

The surrounding magnet structures 6A and 6D enhance the magnetic fluxes Φ1 and Φ2 and the detection magnetic fluxes DF1 and DF2. Enclosing the magnet structure 6A, in the magnetic path through which magnetic fluxes flow Φ1 and the detected magnetic flux DF2, added magnetomotive force of the same polarity and enclose the magnet structure 6 B, enhances the flux Φ1 and the detected magnetic flux DF2. The surrounding magnet structure 6D adds a magnetomotive force having the same polarity as that of the surrounding magnet structure 6C in the magnetic path through which the magnetic flux Φ2 and the detection magnetic flux DF1 flow, thereby enhancing the magnetic flux Φ2 and the detection magnetic flux DF1.

  In the second embodiment, in addition to the same effects as in the first embodiment, both the detection magnetic fluxes DF1 and DF2 can be enhanced. Therefore, the magnitude of the bipolar type output signal of the magnetic sensor 15 is increased, and the large bipolar type output signal is obtained. The torque sensor with higher sensitivity can be realized.

Embodiment 3 FIG.
13 to 16 show a third embodiment of the torque sensor according to the present invention. FIG. 13 is a vertical cross-sectional view of a plane including the common axis LL similar to FIGS. 2, 5, and 12, and is a vertical cross-sectional view in the positive torque range of the torque sensor of the third embodiment. 14 is a sectional view of the stage A along the line AA in FIG. 13, FIG. 15 is a sectional view of the stages B and C along the line BB and CC in FIG. 13, and FIG. It is sectional drawing of the stage D by a line.

  In the third embodiment, among the four magnetic field changing means 31 to 34 in the first embodiment, the magnetic field changing means 32 and 33 in the stages B and C are changed to magnetic field forming means 32A and 33A, respectively. The other configuration is the same as that of the first embodiment. In the third embodiment, the magnetic field changing means 31 and 34 are arranged on the stages A and D, respectively, and the enclosing magnet structures 6B and 6C constituting the magnetic field generating means 6 are arranged on the stages B and C, respectively. Magnetic field forming means 32A and 33A are arranged.

  The magnetic field changing means 31 in the stage A shown in FIG. 14 is configured the same as the magnetic field changing means 31 in the first embodiment shown in FIG. 7, and the magnetic field changing means 34 in the stage D shown in FIG. 16 is shown in FIG. The configuration is the same as the magnetic field changing means 34 in the first embodiment. 14 and 16 show a state in which the torque sensor of the third embodiment is in the positive torque range, and the inner peripheral magnetic poles 11a and 11d are away from the angular position θ2 and approach the angular position θ1.

In the third embodiment, as shown in FIG. 15, the magnetic field forming means 32A and 33A are configured so that the inner peripheral magnetic poles 11b and 11c and the outer peripheral magnetic poles 14b and 14c do not have protruding magnetic poles. 11c and outer magnetic poles 14b and 14c are configured to have ring-shaped magnetic pole surfaces around the common axis LL, and between the inner magnetic poles 11b and 11c and the outer magnetic poles 14b and 14c. voids uniformly sized along about a common axis L-L are formed. Therefore, in the third embodiment, the magnetic field changing means 31 and 34 give the same magnetic field change as in the first embodiment to the relative rotation between the inner peripheral cylinder 3 and the outer peripheral rotating body 12, and change the magnetic fluxes Φ1 and Φ2. The detection magnetic fluxes DF1 and DF2 are generated, but the magnetic field forming means 32A and 33A do not change the magnetic field.

  In the third embodiment, the gap length between the inner peripheral magnetic poles 11b and 11c and the outer peripheral magnetic poles 14b and 14c in the magnetic field forming means 32A and 33A is configured to be sufficiently smaller than that in the first embodiment. The For this reason, in the third embodiment, since the magnetic fluxes Φ1 and Φ2 and the detected magnetic fluxes DF1 and DF2 are larger than those in the first embodiment, the output signal is also larger in the bipolar type of the magnetic sensor 15 and the torque with higher sensitivity is obtained. A sensor can be realized.

Embodiment 4 FIG.
17 and 18 show a torque sensor according to a fourth embodiment of the present invention. 17 is a longitudinal sectional view of a plane including the common axis LL similar to FIG. 13, and FIG. 18 is a sectional view of the stages B and C along the BB and CC lines of FIG.

  In the fourth embodiment, similarly to the third embodiment, the magnetic field forming means 32A and 33A are provided on the stages B and C. In these magnetic field forming means 32A and 33A, the inner peripheral magnetic poles 11b and 11c are provided. Are deleted, and the magnetic field forming means 32A and 33A are constituted by the surrounding magnet structures 6B and 6C and the outer peripheral magnetic poles 14b and 14c, respectively. The other configuration is the same as that of the first embodiment. In the fourth embodiment, the magnetic field changing means 31 and 34 are arranged on the stages A and D, respectively, and the enclosing magnet structures 6B and 6C constituting the magnetic field generating means 6 are arranged on the stages B and C, respectively. Magnetic field forming means 32A and 33A are arranged.

  In the fourth embodiment, the magnetic field forming means 32A is constituted by the surrounding magnet structure 6B and the outer peripheral magnetic pole 14b, and the outer peripheral magnetic pole surface 62b of the ring-shaped permanent magnet 62 of the surrounding magnet structure 6B is directly connected to the outer peripheral magnetic pole 14b through the air gap. Opposite to. Similarly, the magnetic field forming means 33A is constituted by the surrounding magnet structure 6C and the outer peripheral magnetic pole 14c, and the outer peripheral magnetic pole surface 63b of the ring-shaped permanent magnet 63 of the surrounding magnet structure 6C is directly opposed to the outer peripheral magnetic pole 14b through a gap. Yes. In the stages B and C, the ring-shaped iron cores 7 and 8 are fixed to the outer peripheral surface of the inner peripheral cylinder 3, and the ring-shaped permanent magnets 62 and 63 are fixed to the outer periphery of the ring-shaped iron cores 7 and 8.

In the fourth embodiment, as shown in FIG. 18, the outer peripheral magnetic pole surfaces 62b and 63b and the outer peripheral magnetic poles 14b and 14c of the ring-shaped permanent magnets 62 and 63 have no projecting magnetic poles, and the outer peripheral magnetic pole surfaces 62b, 63b and outer peripheral magnetic poles 14b and 14c are each configured to have a ring-shaped magnetic pole surface around the common axis LL, and the outer peripheral magnetic pole surfaces 62b and 63b of the ring-shaped permanent magnets 62 and 63, outer peripheral magnetic pole 14b, between 14c, the gap having a uniform size along the circumference of the common axis L-L are formed.

  In the fourth embodiment, gaps are formed between the outer peripheral magnetic pole surfaces 62b and 63b of the ring-shaped permanent magnets 62 and 63 and the outer peripheral magnetic poles 14b and 14c, and the outer peripheral magnetic pole surfaces 62b and 63b of the permanent magnets 62 and 63 are formed. Since the magnetic flux from the outer peripheral magnetic pole surfaces 62b and 63b is directly exposed in the radial direction centered on the common axis LL, the leakage magnetic flux in the permanent magnets 62 and 63 is reduced as a result. Compared to the first embodiment, the magnetic fluxes Φ1 and Φ2 and the detected magnetic fluxes DF1 and DF2 are increased, the bipolar type output signal of the magnetic sensor 15 is increased, and a more sensitive torque sensor can be realized.

Embodiment 5 FIG.
19 to 23 show a torque sensor according to a fifth embodiment of the present invention. FIG. 19 is a longitudinal sectional view of a plane including a common axis LL similar to FIGS. 2, 5, 12, 13, and 17, and is a longitudinal section in the positive torque range of the torque sensor of the fifth embodiment. FIG. 20 is a sectional view of the stage A along the line AA in FIG. 19, FIG. 21 is a sectional view of the stage B along the line BB in FIG. 19, and FIG. 22 is a sectional view of the stage C along the line CC in FIG. FIG. 23 is a sectional view of the stage D along the line DD in FIG.

  In the fifth embodiment, the surrounding magnet structures 6B and 6C in the stages B and C in the first embodiment are configured by the ring-shaped permanent magnets 65 and 66 shown in FIGS. The permanent magnets 65 and 66 are fixed to the outer periphery of the ring-shaped iron cores 7 and 8 fixed to the inner peripheral cylinder 3, and the inner peripheral magnetic poles 11b and 11c in the first embodiment are deleted. The other configuration is the same as that of the first embodiment. In the fifth embodiment, the magnetic field changing means 31 and 34 are arranged on the stages A and D, respectively, and the surrounding magnet structures 6B and 6C constituting the magnetic field generating means 6 are arranged on the stages B and C, respectively. Magnetic field changing means 32 and 33 are arranged.

  As shown in FIGS. 21 and 22, the ring-shaped permanent magnets 65 and 66 are ring-shaped permanent magnets in which projecting magnetic poles 65A and 66A are integrally formed on the outer circumference so as to surround the common axis LL. Be placed. The ring-shaped permanent magnet 65 disposed on the stage B has an inner peripheral magnetic pole surface 65a, an outer peripheral magnetic pole surface 65b, and an intermediate surface 65c formed therebetween. Similarly, the ring-shaped permanent magnet 66 arranged on the stage C has an inner peripheral magnetic pole surface 66a, an outer peripheral magnetic pole surface 66b, and an intermediate surface 66c formed between them. These ring-shaped permanent magnets 65 and 66 are magnetized in the radial direction centered on the common axis LL so that the inner peripheral side is an S pole and the outer peripheral side is an N pole.

  As shown in FIG. 21, a plurality of protruding magnetic poles 65A are formed on the outer periphery of the ring-shaped permanent magnet 65 at equal angular intervals. Specifically, nine protruding magnetic poles 65A are integrally formed with the ring-shaped permanent magnet 65 at an angular interval of 40 degrees. As shown in FIG. 22, a plurality of protruding magnetic poles 66 </ b> A are similarly formed on the outer periphery of the ring-shaped permanent magnet 66 at equal angular intervals. Specifically, nine protruding magnetic poles 66A are integrally formed with the ring-shaped permanent magnet 66 at an angular interval of 40 degrees. These protruding magnetic poles 65A and 66A are in phase with the inner peripheral magnetic poles 11a and 11d in the same manner as the inner peripheral magnetic poles 11b and 11c in the first embodiment, for example, from the inner peripheral magnetic pole reference position around the common axis LL. They are arranged at angular positions of 0 degrees, 40 degrees, 80 degrees, 120 degrees, 160 degrees, 200 degrees, 240 degrees, 280 degrees, and 320 degrees.

  The inner peripheral magnetic pole surfaces 65a, 66a of the ring-shaped permanent magnets 65, 66 are peripheral surfaces that are continuous around the common axis LL, and only the S poles are provided around the common axis LL. It is formed continuously. The outer peripheral magnetic pole surfaces 65b and 66b are intermittently formed on the outer periphery of each of the projecting magnetic poles 65A and 66A at an angular interval of 40 degrees, and the outer peripheral magnetic pole surfaces 65b and 66b have a common axis LL. Surrounds it as the center. In these outer peripheral magnetic pole surfaces 65b and 66b, only the N pole is intermittently formed around the common axis LL.

  The intermediate surface 65c is formed between the adjacent projecting magnetic poles 65A of the nine projecting magnetic poles 65A around the common axis LL. Similarly, the intermediate surface 66c is formed between the adjacent projecting magnetic poles 66A of the nine projecting magnetic poles 66A around the common axis LL. The intermediate surfaces 65c and 66c are intermittently formed around the common axis LL at an angular interval of 40 degrees around each other.

  20 to 23 show that the torque sensor of the fifth embodiment is in the positive torque range, and the inner peripheral magnetic poles 11a and 11d and the protruding magnetic poles 65A and 66A move away from the angular position θ2 and approach the angular position θ1. It shows the state in the position. In this state, the detection magnetic flux DF1 is generated between the stage B and the stage D. The detected magnetic flux DF2 is generated between the stage A and the stage C in the negative torque range in which the inner peripheral magnetic poles 11a and 11d and the projecting magnetic poles 65A and 66A move away from the angular position θ1 and approach the angular position θ2. As a result, also in the fifth embodiment, the magnetic sensor 15 can obtain a bipolar type output signal.

  In the torque sensor of the fifth embodiment, the surrounding magnet structures 6B and 6C arranged on the stages B and C are configured by ring-shaped permanent magnets 65 and 66 each having a plurality of protruding magnetic poles 65A and 66A formed on the outer periphery. Is done. These ring-shaped permanent magnets 65, 66 have only one magnetic pole of the N and S poles around the common axis LL on the outer peripheral magnetic pole faces 65b, 66b. Are arranged on the inner peripheral magnetic pole surfaces 65a, 66a around the common axis LL so that only the magnetic pole of the other polarity of the two magnetic poles is arranged around the common axis LL. As the conventional magnet structure is magnetized in the radial direction, the deviation of the zero point of the output signal due to the deviation of the boundary between the N pole and the S pole on the same peripheral surface is eliminated, and the stable zero point An output signal having an output can be obtained.

  Further, gaps are formed between the outer peripheral magnetic pole surfaces 65b and 66b of the ring-shaped permanent magnets 65 and 66 and the outer peripheral magnetic poles 14b and 14c, and the outer peripheral magnetic pole surfaces 65b and 66b of the permanent magnets 65 and 66 are exposed to these gaps. Since the magnetic fluxes from the outer peripheral magnetic pole surfaces 65b and 66b directly go out in the radial direction centered on the common axis LL, the magnetic fluxes Φ1 and Φ2 and the detected magnetic fluxes DF1 and DF2 are compared with those in the first embodiment. As a result, the bipolar type output signal of the magnetic sensor 15 is increased, and a torque sensor with higher sensitivity can be realized.

Embodiment 6 FIG.
24 and 25 show Embodiment 6 of the torque sensor according to the present invention. FIG. 24 is a cross-sectional view of the stage B of the sixth embodiment, and FIG. 25 is a cross-sectional view of the stage C. 24 and 25 are cross-sectional views taken along a plane orthogonal to the common axis LL.

  In the sixth embodiment, the surrounding magnet structures 6B and 6C in the stages B and C in the first embodiment are configured by the ring-shaped magnet bodies 67 and 68 shown in FIGS. 68 are fixed to the outer periphery of the ring-shaped iron cores 7 and 8 fixed to the inner peripheral cylinder 3, and the inner peripheral magnetic poles 11b and 11c in the first embodiment are deleted. The other configuration is the same as that of the first embodiment.

As shown in FIGS. 24 and 25, a plurality of magnetized areas 67A and 68A are formed in these ring-shaped magnet bodies 67 and 68 at equal angular intervals around the common axis LL. The plurality of magnetized areas 67A and 68A are magnetized in the radial direction centered on the common axis LL, with the inner peripheral side being the S pole and the outer peripheral side being the N pole. The ring-shaped magnet body 67 arranged on the stage B is arranged so as to surround the common axis LL, and has an inner peripheral magnetic pole surface 67a and an outer peripheral magnetic pole surface 67b around the common axis LL. A plurality of magnetized areas 67A of the ring-shaped magnet body 67 extend in the radial direction about the common axis LL between the inner peripheral magnetic pole surface 67a and the outer peripheral magnetic pole surface 67b. Due to the plurality of magnetized areas 67A, only the S pole is intermittently formed around the common axis LL on the inner peripheral magnetic pole surface 67a, and only the N pole is formed on the outer peripheral magnetic pole surface 67b. Formed intermittently around L.

Similarly, the ring-shaped magnet body 68 disposed on the stage C is disposed so as to surround the common axis LL, and has an inner peripheral magnetic pole surface 68a and an outer peripheral magnetic pole surface 68b around the common axis LL. . A plurality of magnetized areas 68A of the ring-shaped magnet body 68 extend in the radial direction about the common axis LL between the inner peripheral magnetic pole surface 68a and the outer peripheral magnetic pole surface 68b. Due to the plurality of magnetized areas 68A, only the S pole is intermittently formed around the common axis LL on the inner peripheral magnetic pole surface 68a, and only the N pole is formed on the outer peripheral magnetic pole surface 68b. Formed intermittently around -L. Note that the magnetic material remains between the adjacent magnetized areas 67A and between the adjacent magnetized areas 68A without being magnetized.

  Specifically, as shown in FIG. 24, nine magnetized areas 67A are formed at an angular interval of 40 degrees from each other in the plurality of magnetized areas 67A. As shown in FIG. 25, the plurality of magnetized areas 68A are also formed with nine magnetized areas 68A at an angular interval of 40 degrees. The plurality of magnetized areas 67A and 68A are in the same phase as the inner peripheral magnetic poles 11a and 11d in the same manner as the inner peripheral magnetic poles 11b and 11c in the first embodiment, and the inner peripheral magnetic pole reference position around the common axis LL. From, for example, the angle positions of 0 degrees, 40 degrees, 80 degrees, 120 degrees, 160 degrees, 200 degrees, 240 degrees, 280 degrees, and 320 degrees are formed. 24 and 25 show a state in which the torque sensor of the sixth embodiment is in the positive torque range, and the magnetized areas 67A and 68A are away from the angular position θ2 and approach the angular position θ1.

  Also in the sixth embodiment, the torque sensor is in the positive torque range, and the inner peripheral magnetic poles 11a and 11d and the magnetized areas 67A and 68A are located away from the angular position θ2 and close to the angular position θ1. In the state, the detection magnetic flux DF1 is generated between the stage B and the stage D, and the inner peripheral magnetic poles 11a and 11d and the magnetized areas 67A and 68A are away from the angular position θ1 and are negatively approaching the angular position θ2. In the torque range, the detection magnetic flux DF2 is generated between the stage A and the stage C. As a result, also in the sixth embodiment, the magnetic sensor 15 can obtain a bipolar type output signal.

Also in the torque sensor of the sixth embodiment, the ring-shaped magnet bodies 67 and 68 have both N-pole and S-pole magnetic poles on the outer peripheral magnetic pole surfaces 67b and 68b along the common axis LL. Only one of the magnetic poles of the two magnetic poles is intermittently arranged on the inner peripheral magnetic pole surfaces 67a and 68a along the common axis LL. Because it is lined up like the conventional magnet structure, it eliminates the deviation of the zero point of the output signal due to the deviation of the boundary between N pole and S pole on the same peripheral surface, and bipolar type with stable zero point output Output signal can be obtained.

Embodiment 7 FIG.
FIG. 26 shows a seventh embodiment of the torque sensor according to the present invention. FIG. 26 is a top view at the origin position according to the seventh embodiment, but some components are omitted in order to make the drawings easy to see, as in FIGS.

  In the seventh embodiment, as the surrounding magnet structures 6B and 6C arranged on the stages B and C, as shown in FIG. 26, a magnet ring arrangement 69 composed of a plurality of permanent magnet pieces 69A is used. The magnet ring arrangement 69 is arranged inside the ring-shaped iron core 7 fixed to the outer periphery of the inner peripheral cylinder 3 in the stage B, and inside the ring-shaped iron core 8 fixed to the outer periphery of the inner peripheral cylinder 3 in the stage C. Placed in. The other configuration is the same as that of the first embodiment.

  As shown in FIG. 26, the magnet ring arrangement 69 includes a plurality of, for example, nine permanent magnet pieces 69A, and the plurality of permanent magnet pieces 69A have the same circumference around the common axis LL. Arranged side by side. The magnet ring arrangement 69 has an inner peripheral magnetic pole surface 69a and an outer peripheral magnetic pole surface 69b around the common axis LL. The inner peripheral magnetic pole surface 69a is a magnetic pole surface including the inner peripheral side end surfaces of the plurality of permanent magnet pieces 69A, and the outer peripheral magnetic pole surface 69b is a magnetic pole surface including these outer peripheral side end surfaces. Each of the plurality of permanent magnet pieces 69A is magnetized in the radial direction about the common axis LL so that the inner peripheral end faces are all S poles and the outer peripheral end faces are all N poles. Is done. Accordingly, only the south pole is intermittently formed around the common axis LL on the inner circumferential magnetic pole surface 69a of the magnet ring arrangement 69, and the outer circumferential magnetic pole surface 69b has the common axis LL. Only N poles are intermittently formed along the periphery. Ring-shaped iron cores 7 and 8 are interposed between adjacent permanent magnet pieces 69A.

  Also in the seventh embodiment, since the surrounding magnet structures 6B and 6C are arranged on the stages B and C to constitute the magnetic field generating means 6, the bipolar sensor outputs the bipolar type output signal by the magnetic sensor 15 as in the first embodiment. Since the same polarity magnetic poles are intermittently arranged on the inner peripheral magnetic pole surface 69a and the outer peripheral magnetic pole surface 69b of the magnet ring arrangement 69, a bipolar type output signal having a stable zero point output can be generated. Obtainable.

Embodiment 8 FIG.
27 to 32 show a torque sensor according to an eighth embodiment of the present invention. FIG. 27 is a top view at the origin position of the torque sensor according to the eighth embodiment, but some parts are omitted for easy understanding of the drawings as in FIGS. FIG. 28 is a longitudinal sectional view of a plane including the common axis LL, and is a longitudinal sectional view in the positive torque range of the torque sensor of the eighth embodiment. 29 is a sectional view of the stage A along the line AA in FIG. 28, FIG. 30 is a sectional view of the stage B along the line BB in FIG. 28, and FIG. 31 is a sectional view of the stage C along the line CC in FIG. 32 is a sectional view of the stage D along the line DD in FIG.

  As shown in FIG. 30, the eighth embodiment uses a magnet ring arrangement 72 composed of a plurality of permanent magnet pieces 72A as the surrounding magnet structure 6B arranged on the stages B and C of the first embodiment. Further, as the surrounding magnet structure 6C arranged on the stage C, as shown in FIG. 31, a magnet ring arrangement 73 composed of a plurality of permanent magnet pieces 73A is used. The magnet ring arrangement 72 is arranged on the outer periphery of the ring-shaped iron core 7 fixed to the outer periphery of the inner peripheral cylinder 3 in the stage B, and the magnet ring arrangement 73 is a ring fixed to the outer periphery of the inner peripheral cylinder 3 in the stage C. The inner peripheral magnetic poles 11b and 11c of the first embodiment are deleted from the outer periphery of the iron core 8. The other configuration is the same as that of the first embodiment. In the eighth embodiment, the magnetic field changing means 31 and 34 are arranged on the stages A and D, respectively, and the surrounding magnet structures 6B and 6C and the magnetic field changing means 32 and 33 are arranged on the stages B and C, respectively. .

  As shown in FIG. 30, the magnet ring arrangement 72 is constituted by a plurality of, for example, nine permanent magnet pieces 72A, and the plurality of permanent magnet pieces 72A are ring-shaped iron cores centered on the common axis LL. 7 are arranged side by side at a predetermined angular interval on the outer peripheral surface of 7. The magnet ring arrangement 72 has an inner peripheral magnetic pole surface 72a and an outer peripheral magnetic pole surface 72b around the common axis LL. The inner peripheral magnetic pole surface 72a is a magnetic pole surface including the inner peripheral side end surfaces of the plurality of permanent magnet pieces 72A, and the outer peripheral magnetic pole surface 72b is a magnetic pole surface including these outer peripheral side end surfaces. Each of the plurality of permanent magnet pieces 72A is magnetized in the radial direction centered on the common axis LL so that the inner peripheral side end faces are all S poles and the outer peripheral side end faces are all N poles. Is done. Therefore, only the south pole is intermittently formed along the circumference of the common axis LL on the inner circumferential magnetic pole surface 72a of the magnet ring arrangement 72, and the outer circumferential magnetic pole surface 72b has the common axis LL. Only N poles are intermittently formed along the periphery. In addition, between the adjacent permanent magnet pieces 72A, the magnetic body surface 7a on the outer periphery of the ring-shaped iron core 7 which is a magnetic body is exposed. The magnetic surface 7a has a smaller diameter than the outer magnetic pole surface 72b.

  As shown in FIG. 31, the magnet ring arrangement 73 is composed of a plurality of, for example, nine permanent magnet pieces 73A, and the plurality of permanent magnet pieces 73A are ring-shaped iron cores centered on a common axis LL. 8 are arranged side by side at a predetermined angular interval on the outer peripheral surface. The magnet ring arrangement 73 has an inner peripheral magnetic pole surface 73a and an outer peripheral magnetic pole surface 73b around the common axis LL. The inner peripheral magnetic pole surface 73a is a magnetic pole surface including the inner peripheral side end surfaces of the plurality of permanent magnet pieces 73A, and the outer peripheral magnetic pole surface 73b is a magnetic pole surface including these outer peripheral side end surfaces. Each of the plurality of permanent magnet pieces 73A is magnetized in the radial direction centered on the common axis LL so that the inner peripheral end faces are all S poles and the outer peripheral end faces are all N poles. Is done. Therefore, only the south pole is intermittently formed along the circumference of the common axis LL on the inner circumferential magnetic pole surface 73a of the magnet ring arrangement 73, and the outer circumferential magnetic pole surface 73b has the common axis LL. Only N poles are intermittently formed along the periphery. In addition, between the adjacent permanent magnet pieces 73A, the magnetic body surface 8a on the outer periphery of the ring-shaped iron core 8 which is a magnetic body is exposed. The magnetic surface 8a has a smaller diameter than the outer magnetic pole surface 73b.

  Specifically, in the magnet ring arrangement 72, nine permanent magnet pieces 72A are arranged at an angular interval of 40 degrees from each other, as shown in FIG. Also in the magnet ring arrangement 73, as shown in FIG. 31, nine permanent magnet pieces 73A are arranged at an angular interval of 40 degrees from each other. The plurality of permanent magnet pieces 72A and 73A are arranged in the same phase as the inner peripheral magnetic poles 11a and 11d in the same manner as the inner peripheral magnetic poles 11b and 11c in the first embodiment, and the inner peripheral magnetic pole reference position around the common axis LL. From, for example, the angle positions of 0 degrees, 40 degrees, 80 degrees, 120 degrees, 160 degrees, 200 degrees, 240 degrees, 280 degrees, and 320 degrees are formed.

  29 to 32 show that the torque sensor according to the eighth embodiment is in the positive torque range, and the inner peripheral magnetic poles 11a and 11d and the permanent magnet pieces 72A and 73A are moved away from the angular position θ2 and moved to the angular position θ1. Indicates the state at an approaching position. In this state, the detection magnetic flux DF1 is generated between the stage B and the stage D. The detected magnetic flux DF2 is generated between the stage A and the stage C in the negative torque range in which the inner peripheral magnetic poles 11a and 11d and the projecting magnetic poles 72A and 73A move away from the angular position θ1 and approach the angular position θ2. As a result, also in the eighth embodiment, the magnetic sensor 15 can obtain a bipolar type output signal.

  Also in the torque sensor of the eighth embodiment, the magnet ring arrangements 72 and 73 have both the N-pole and S-pole magnetic poles on the outer peripheral magnetic pole surfaces 72b and 73b around the common axis LL. Only the magnetic poles of one of the polarities are intermittently arranged, and only the magnetic poles of the other polarity of the two magnetic poles are intermittently arranged on the inner peripheral magnetic pole surfaces 72a and 73a along the common axis LL. Therefore, a torque sensor having a stable zero point output can be obtained.

  In the eighth embodiment, the plurality of permanent magnet pieces 72A and 73A and the outer peripheral magnetic poles 14b and 14c are opposed to each other through a gap, and the plurality of permanent magnet pieces 72A and 73A are directly exposed to the gap. As a result, the gap length in the radial direction of the gap is substantially increased, and the output signal of the magnetic sensor 15 is prevented from being saturated outside the positive and negative torque ranges, and the linearity of the output signal is improved. can do.

  Each of the plurality of permanent magnet pieces 72A and 73A can be formed in an arc plate shape along the outer peripheral surface of the ring-shaped iron cores 7 and 8, or can be formed in a flat plate shape. These permanent magnet pieces 72A and 73A are fixed to the outer peripheral surfaces of the ring-shaped iron cores 7 and 8 by adhesion or the like. In addition, the magnetic pole property of each of the permanent magnet pieces 72A and 73A can be changed so that the inner peripheral side end faces are all N poles and the outer peripheral side end faces are all S poles in the opposite manner.

Embodiment 9 FIG.
FIG. 33 is a top view of the origin of the torque sensor according to the ninth embodiment of the present invention. In the ninth embodiment, in the stages B and C of the eighth embodiment, the magnet ring arrangements 72 and 73 are modified so as to be fitted into the recesses formed on the outer peripheral surfaces of the ring-shaped iron cores 7 and 8. The other configuration is the same as that of the eighth embodiment. According to the ninth embodiment, the same effect as in the eighth embodiment can be obtained.

  FIG. 33 is a top view of the ninth embodiment, but in the same manner as FIGS. 1 and 4, some parts are omitted in order to make the drawings easy to see. In the ninth embodiment, in stages B and C, a plurality of, for example, nine recesses 7b and 8b are provided on the outer peripheral surface of the ring-shaped iron cores 7 and 8 along the peripheral surface at an angular interval of 40 degrees. Nine permanent magnet pieces 72A and 73A constituting the magnet ring arrangements 72 and 73 are fitted and fixed in these recesses 7b and 8b. Nine permanent magnet pieces 72A constituting the magnet ring arrangement 72 are fitted into the recess 7b on the outer peripheral surface of the ring-shaped iron core 7 of the stage B. Similarly, the recess 8b on the outer peripheral surface of the ring-shaped iron core 8 of the stage C is inserted. The nine permanent magnet pieces 73A constituting the magnet ring arrangement 73 are fitted and fixed. Between the adjacent permanent magnet pieces 72A and 73A, the magnetic surfaces 7a and 8a on the outer periphery of the ring-shaped iron cores 7 and 8 are exposed. These magnetic surfaces 7a and 8a have a smaller diameter than the outer peripheral magnetic pole surfaces 72b and 73b constituted by the outer peripheral surfaces of the permanent magnet pieces 72A and 73A.

Embodiment 10 FIG.
FIG. 34 shows a torque sensor according to a tenth embodiment of the present invention. FIG. 34 is a top view of the tenth embodiment and shows a state in which the torque sensor is at the origin position, but parts are omitted in order to make the drawing easier to see as in FIGS. .

  In the tenth embodiment, inclined surfaces 16a and 16b are formed on the respective magnetic pole surfaces of the inner peripheral magnetic poles 11a, 11b, 11c, and 11d in the same phase as in the first embodiment, as shown in FIG. . In addition, the outer peripheral magnetic poles 14a and 14c that are in phase with each other are arranged so as to face the clockwise side ends of the inner peripheral magnetic poles 11a, 11b, 11c, and 11d, and the outer peripheral magnetic poles 14b and 14d that are in phase with each other The inner peripheral magnetic poles 11a, 11b, 11c, and 11d are arranged so as to face the counterclockwise ends, and at the same time, inclined surfaces 16d are formed on the respective magnetic pole surfaces of the outer peripheral magnetic poles 14b and 14d. , 14c, inclined surfaces 16c are formed on the magnetic pole surfaces. The rest is the same as in the first embodiment, and the surrounding magnet structures 6B and 6C configured by the ring-shaped permanent magnets 62 and 63 are used as the magnetic field generating means 6 in the stages B and C.

The inclined surfaces 1 6 a and 1 6 b of the magnetic pole surfaces of the inner peripheral magnetic poles 11 a, 11 b, 11 c and 11 d have the highest magnetic pole surface at the center in the circumferential direction of each magnetic pole surface, and the inclined surface 16 a The magnetic pole surfaces are inclined downward from the central portion in the clockwise direction, and the inclined surface 16b is inclined so as to lower the magnetic pole surfaces in the counterclockwise direction from the central portion. The inclined surfaces 16c of the outer peripheral magnetic poles 14a and 14c are opposed to the inclined surfaces 16a of the inner peripheral magnetic poles 11a, 11b, 11c and 11d via a gap, and the inclined surfaces 16d of the outer peripheral magnetic poles 14b and 14d are The inclined surfaces 16b of 11a, 11b, 11c, and 11d are opposed to each other through a gap. The inclined surfaces 16a, 16b, 16c, and 16d are, for example, linear inclined surfaces, but may be curved inclined surfaces.

When the torque acting on the torque sensor changes and the rotary shafts 1 and 2 rotate relatively, the facing area between the inclined surface 1 6 a and the inclined surface 1 6 c changes, and the gap length between them also changes. Change. At the same time, the facing area between the inclined surface 16b and the inclined surface 16d changes, and the gap length between them also changes. Therefore, the change in magnetic resistance between the inner peripheral magnetic poles 11a, 11b, 11c, 11d and the outer peripheral magnetic poles 14a, 14c, and the magnetic resistance between the inner peripheral magnetic poles 11a, 11b, 11c, 11d and the outer peripheral magnetic poles 14b, 14d. Since the change in resistance becomes larger than that in the first embodiment, the bipolar type output signal of the magnetic sensor 15 can be made larger.

Embodiment 11 FIG.
FIG. 35 shows Embodiment 11 of the torque sensor according to the present invention. FIG. 35 is a top view of the eleventh embodiment and shows a state in which the torque sensor is at the origin position, but parts are omitted in order to make the drawing easier to see as in FIGS. .

In the eleventh embodiment, the inner circumferential magnetic poles 11a, 11b, 11c, 11d and the outer circumferential magnetic poles 14a, 14c and the outer circumferential magnetic poles 14b, 14d are both lengthened in the radial direction , and the inner circumferential magnetic pole 11a. 11b, 11c, 11d and the outer peripheral magnetic poles 14a, 14b, 14c, 14d are opposed to each other with a gap in the circumferential direction. The rest is the same as in the first embodiment, and the surrounding magnet structures 6B and 6C configured by the ring-shaped permanent magnets 62 and 63 are used as the magnetic field generating means 6 in the stages B and C. In FIG. 35, the number of projecting magnetic poles of each of the inner peripheral magnetic poles 11a, 11b, 11c, and 11d and the outer peripheral magnetic poles 14a, 14b, 14c, and 14d is five. As in the first embodiment, the number of protruding magnetic poles is nine. Note that the number of these projecting magnetic poles may be other than 5, 9 or, for example, 6, 7, 8, 10, 11 or the like.

  In the eleventh embodiment, the outer peripheral magnetic poles 14a and 14c that are in phase with each other are arranged on the clockwise sides of the inner peripheral magnetic poles 11a, 11b, 11c, and 11d, and the outer peripheral magnetic poles 14b and 14d that are in phase with each other are It arrange | positions at the counterclockwise direction side part of the inner peripheral magnetic pole 11a, 11b, 11c, 11d. When the torque acting on the torque sensor changes and the rotary shafts 1 and 2 rotate relatively, the circumferential gap between the inner peripheral magnetic poles 11a, 11b, 11c, 11d and the outer peripheral magnetic poles 14a, 14c, and the inner The circumferential gaps between the circumferential magnetic poles 11a, 11b, 11c, 11d and the outer circumferential magnetic poles 14b, 14d change in opposite directions, and the magnetic resistances in the respective gaps also change in opposite directions. Also in the eleventh embodiment, a bipolar type output signal can be obtained from the magnetic sensor 15.

Embodiment 12 FIG.
36 and 37 show a torque sensor according to a twelfth embodiment of the present invention. FIG. 36 is a front view of the twelfth embodiment, and FIG. 37 is a side view thereof.

  In the twelfth embodiment, the protrusions 12c and 12d of the outer peripheral cylinders 12a and 12b are deleted from the first embodiment, and the connecting body 13 that connects the outer peripheral cylinders 12a and 12b is changed to a connecting body 13a. A pair of magnetic aggregation members 17A and 17B are arranged on the outer periphery of 13a, and the magnetic sensor 15 is arranged between these magnetic aggregation members 17A and 17B. The rest of the configuration is the same as in the first embodiment, and the surrounding magnet structures 6B and 6C configured by the ring-shaped permanent magnets 62 and 63 are used as the magnetic field generating means 6 in the stages B and C.

  The connecting body 13a is formed in a cylindrical shape using a nonmagnetic material such as aluminum, and is joined to the inner peripheral surfaces thereof so as to straddle the outer peripheral cylinder 12a and the outer peripheral cylinder 12b. On the outer periphery of the coupling body 13a, an annular groove 13b is formed between the end faces of the outer peripheral cylinders 12a and 12b, and the magnetic concentrating members 17A and 17B are disposed in the annular groove 13b. As shown in FIGS. 36 and 37, the magnetic aggregation members 17A and 17B are each formed in a trapezoidal shape, and have a long side 17a and a short side 17b that face each other in parallel. The long sides 17a of the magnetic concentrating members 17A and 17B are opposed to the outer peripheral cylinders 12a and 12b, respectively, through a minute gap. The short sides 17b of the magnetic aggregation members 17A and 17B are opposed to each other, and the magnetic sensor 15 is disposed between them. The magnetic concentrating members 17A and 17B constitute the detection magnetic path 20 between the outer peripheral cylinders 12a and 12b, consolidate the detection magnetic fluxes DF1 and DF2 on the short side 17b, and effectively collect the collected detection magnetic fluxes DF1 and DF2. This is given to the magnetic sensor 15.

  The outer peripheral cylinders 12a and 12b and the coupling body 13a rotate around the common axis LL, but the magnetic aggregation members 17A and 17B and the magnetic sensor 15 are fixed with respect to the absolute space. According to this configuration, the tangling of the lead wire with respect to the magnetic sensor 15 can be eliminated, and the disconnection associated with the rotation of the outer peripheral cylinders 12a, 12b and the coupling body 13a can be avoided.

In the twelfth embodiment, the magnetic concentrating members 17A and 17B are not limited to the trapezoidal shape, but may have other shapes. The magnetic aggregation member 17A, 17B and, more and a magnetic sensor 15, etc. molding resin, can be integrated with each other. The smaller the gap between the short side 17b of each of the magnetic concentrating members 17A and 17B and the magnetic sensor 15, the more effective the aggregated detection magnetic flux DF can be given to the magnetic sensor 15, and each magnetic concentrating member. It is preferable that the gap between the long side 17a of 17A and 17B and the outer peripheral cylinders 12a and 12b is also small.

Embodiment 13 FIG.
FIG. 38 shows a torque sensor according to a thirteenth embodiment of the present invention. FIG. 38 is a front view of the thirteenth embodiment.

  In the thirteenth embodiment, in the first embodiment, the protrusions 12c and 12d of the outer peripheral cylinders 12a and 12b are deleted, and a pair of magnetic aggregation members 17C and 17D are provided on the outer periphery of the connecting body 13 that connects the outer peripheral cylinders 12a and 12b. And the magnetic sensor 15 is disposed between the magnetic concentrating members 17C and 17D. The rest of the configuration is the same as in the first embodiment, and the surrounding magnet structures 6B and 6C configured by the ring-shaped permanent magnets 62 and 63 are used as the magnetic field generating means 6 in the stages B and C.

  The magnetic concentrating members 17C and 17D are opposed to the outer peripheral surfaces of the outer peripheral cylinders 12a and 12b through a minute gap, and the magnetic sensor 15 is disposed between the magnetic concentrating members 17C and 17D. The magnetic concentrating members 17C and 17D constitute a detection magnetic path 20 between the outer peripheral cylinders 12a and 12b, and effectively provide the magnetic fluxes DF1 and DF2 to the magnetic sensor 15.

  Also in the thirteenth embodiment, the outer peripheral cylinders 12a and 12b and the coupling body 13 rotate around the common axis LL, but the magnetic aggregation members 17C and 17D and the magnetic sensor 15 are fixed with respect to the absolute space. . With this configuration, as in the twelfth embodiment, the tangling of the lead wire with respect to the magnetic sensor 15 is eliminated, and the disconnection of the lead wire associated with the rotation of the outer peripheral cylinders 12a, 12b and the coupling body 13a can be avoided.

Embodiment 14 FIG.
FIG. 39 is a top view showing the fourteenth embodiment of the torque sensor according to the present invention at its origin position. 40, 41, and 42 are views showing the torque sensor according to the fourteenth embodiment in the positive torque range. FIG. 39 is a top view of the torque sensor according to the fourteenth embodiment as viewed in the axial direction, but some of the components are omitted for easy viewing of the drawing. FIG. 40 is a longitudinal sectional view of the torque sensor according to the fourteenth embodiment cut along a plane including the common axis LL. 41 is a cross-sectional view taken along line BB in FIG. 40, and FIG. 42 is a cross-sectional view taken along line CC in FIG. Both the BB line and the CC line in FIG. 40 are included in a plane orthogonal to the common axis LL.

In the fourteenth embodiment, the magnet ring arrangement 82 constituted by a plurality of permanent magnet pieces 82A is used as the surrounding magnet structure 6B arranged in the stage B by removing the stages A and D in the first embodiment. As the surrounding magnet structure 6C arranged on the stage C, a magnet ring arrangement 83 composed of a plurality of permanent magnet pieces 83A is used. The magnet ring arrangement 82 is arranged on the outer periphery of the ring-shaped iron core 7 fixed to the outer periphery of the inner peripheral cylinder 3 in the stage B, and the magnet ring arrangement 83 is a ring fixed to the outer periphery of the inner peripheral cylinder 3 in the stage C. The inner peripheral magnetic poles 11b and 11c of the first embodiment are deleted from the outer periphery of the iron core 8. The magnetic field changing means 32 and 33 are constituted by magnet ring arrangements 82 and 83 and outer magnetic poles 14b and 14c, respectively. The magnet ring arrangements 82 and 83 are each constituted by, for example, four permanent magnets 82A and 83A and four magnetic poles 82B and 83B. Correspondingly, the outer peripheral magnetic poles 14b and 14c also have four protruding magnetic poles. Will be changed as follows. The other configuration is the same as that of the first embodiment.

  As shown in FIG. 41, the magnet ring arrangement 82 includes a plurality of, for example, four permanent magnet pieces 82A and four magnetic poles 82B. The four permanent magnet pieces 82A are adjacent to each other. The magnetic poles 82B are positioned in the middle of the permanent magnet pieces 82A, and are arranged side by side at a predetermined angular interval on the outer peripheral surface of the ring-shaped iron core 7 centered on the common axis LL. The magnetic pole 82B is made of a magnetic material such as iron. The magnet ring arrangement 82 has an inner peripheral magnetic pole surface 82a and an outer peripheral magnetic pole surface 82b around the common axis LL. The inner peripheral magnetic pole surface 82a is a magnetic pole surface including the inner peripheral side end surfaces of the plurality of permanent magnet pieces 82A and the plurality of magnetic poles 82B, and the outer peripheral magnetic pole surface 82b is a magnetic pole surface including these outer peripheral side end surfaces. Each of the plurality of permanent magnet pieces 82A is magnetized in the radial direction about the common axis LL so that the inner peripheral end faces are all S poles and the outer peripheral end faces are all N poles. Is done. Therefore, only the south pole is intermittently formed along the circumference of the common axis LL on the inner circumferential magnetic pole surface 82a of the magnet ring arrangement 82, and the outer circumferential magnetic pole surface 82b has the common axis LL. Only N poles are intermittently formed along the periphery. In addition, between the adjacent permanent magnet piece 82A and the magnetic pole 82B, the magnetic body surface 7a on the outer periphery of the ring-shaped iron core 7 which is a magnetic body is exposed.

  The magnet ring arrangement 83 is configured similarly to the magnet ring arrangement 82. As shown in FIG. 42, the magnet ring arrangement 83 is also composed of a plurality of, for example, four permanent magnet pieces 83A and four magnetic poles 83B. The four permanent magnet pieces 83A are adjacent to the permanent magnet pieces. The magnetic poles 83B are positioned in the middle of 83A, and are arranged side by side at a predetermined angular interval on the outer peripheral surface of the ring-shaped iron core 8 with the common axis LL at the center. The magnetic pole 83B is made of a magnetic material such as iron. The magnet ring arrangement 83 has an inner peripheral magnetic pole surface 83a and an outer peripheral magnetic pole surface 83b around the common axis LL. The inner peripheral magnetic pole surface 83a is a magnetic pole surface including the inner peripheral side end surfaces of the plurality of permanent magnet pieces 83A and the plurality of magnetic poles 83B, and the outer peripheral magnetic pole surface 83b is a magnetic pole surface including these outer peripheral side end surfaces. Each of the plurality of permanent magnet pieces 83A is magnetized in the radial direction about the common axis LL so that the inner peripheral end faces are all S poles and the outer peripheral end faces are all N poles. Is done. Therefore, only the S pole is intermittently formed on the inner peripheral magnetic pole surface 83a of the magnet ring arrangement 83 along the circumference of the common axis LL, and the outer peripheral magnetic pole surface 83b has the common axis LL. Only N poles are intermittently formed along the periphery. In addition, between the adjacent permanent magnet pieces 83A and the magnetic pole 83B, the magnetic body surface 8a on the outer periphery of the ring-shaped iron core 8 which is a magnetic body is exposed.

The magnet ring arrangements 82 and 83 are arranged so that the permanent magnet pieces 82A and 83A overlap each other in the same phase in the direction of the common axis LL. The magnetic poles 82B and 83B are also arranged so as to overlap each other in the direction of the common axis LL. Specifically, in the magnet ring arrangement 82, as shown in FIG. 41, four permanent magnet pieces 82A are arranged at an angular interval of 90 degrees from each other, and just in the middle between the adjacent permanent magnet pieces 82A, respectively. A magnetic pole 82B is disposed. The magnet ring arrangement 83 is the same, and as shown in FIG. 42, four permanent magnet pieces 83A are arranged at an angular interval of 90 degrees from each other, and the magnetic poles 83B are located just in the middle of the adjacent permanent magnet pieces 83A. Be placed. The four permanent magnet pieces 82A of the magnet ring arrangement 82 and the four permanent magnet pieces 83A of the magnet ring arrangement 83 are in phase with each other, for example, from the inner peripheral magnetic pole reference position around the common axis LL, 0 degrees, 90 degrees, 180 degrees, arranged in angular positions 270 degrees, the magnetic rings arranged 82, 83, the inner peripheral magnetic pole reference position, for example, from 45 degrees, 135 degrees, 225 degrees, 315 degrees angular position , Magnetic poles 82B and 83B are disposed, respectively. These angular intervals are 90 degrees, but the number of each permanent magnet piece 82A, 83A can be changed to change the angular interval to other than 90 degrees, for example, 45 degrees, 60 degrees, and the like.

  The outer peripheral magnetic poles 14b and 14c are arranged in an opposite phase relationship to each other as in the first embodiment. However, as a result of changing the outer magnetic poles 14b and 14c to have four protruding magnetic poles, specifically, the outer peripheral magnetic pole 14b. Projecting magnetic poles are formed at angular positions of 0 degrees, 90 degrees, 180 degrees, and 270 degrees from the outer peripheral magnetic pole reference position around the common axis LL, and the outer magnetic pole 14c is formed around the common axis LL. Projecting magnetic poles are formed at angular positions of 45 degrees, 135 degrees, 225 degrees, and 315 degrees from the outer peripheral magnetic pole reference position.

  In the fourteenth embodiment, the magnetic flux from each permanent magnet piece 82A of the magnet ring arrangement 82 is the detected magnetic flux DF1, and the outer peripheral magnetic pole 14b, the outer peripheral cylinder 12a, the detected magnetic path 20, the magnetic sensor 15, the outer peripheral cylinder 12b, and the outer peripheral magnetic pole. 14c, the magnetic pole 83B, the ring-shaped iron core 8, the inner peripheral cylinder 3, and the ring-shaped iron core 7 flow through the magnetic path returning to the magnet ring arrangement 82. Similarly, the magnetic flux from each permanent magnet piece 83A of the magnet ring arrangement 83 is the detected magnetic flux DF2, and the outer peripheral magnetic pole 14c, the outer peripheral cylinder 12b, the detection magnetic path 20, the magnetic sensor 15, the outer peripheral cylinder 12a, the outer peripheral magnetic pole 14b, and the magnetic pole 82B. It flows through the magnetic path returning to the magnet ring arrangement 83 through the ring-shaped iron core 7, the inner peripheral cylinder 3, and the ring-shaped iron core 8.

  In the state where the torque sensor is at the origin position shown in FIG. 39, as shown in FIG. 39, the permanent magnet pieces 82A, 83A of the magnet ring arrangements 82, 83 are located exactly in the middle of the outer magnetic poles 14b and 14c. The magnetic poles 82B and 83B of the magnet ring arrangements 82 and 83 are also located just between the outer peripheral magnetic poles 14b and 14c. For this reason, the detected magnetic fluxes DF1 and DF2 by the permanent magnet pieces 82A and 83A in the magnet ring arrangements 82 and 83 are substantially equal in size and opposite in direction, and therefore cancel each other in the detected magnetic path 20. As a result, the magnetic flux given to the magnetic sensor 15 becomes zero.

If the torque sensor is in the positive torque range, as shown in FIG. 41, each permanent magnet piece 82A in the magnet ring arrangement 82 is moved away from the angular position θ2 and approaches the angular position θ1, as shown in FIG. The 82 permanent magnet pieces 82A approach the outer peripheral magnetic poles 14b, and the magnetic poles 82B move away from the outer peripheral magnetic poles 14b. On the other hand, in stage C, as shown in FIG. 42, each permanent magnet piece 83A in the magnet ring arrangement 83 is moved away from the angular position θ2 and approaches the angular position θ1, so that each permanent magnet 83A in the magnet ring arrangement 83 The magnetic pole 83B moves away from the outer magnetic pole 14c and approaches the outer magnetic pole 14c. As a result, the detected magnetic flux DF1 increases from the permanent magnet pieces 82A of the magnet ring arrangement 82 to the magnetic sensor 15, and the detected magnetic flux DF2 flowing from the permanent magnet pieces 83A of the magnet ring arrangement 83 to the magnetic sensor 15 decreases. 15, a positive output signal is obtained, and the magnitude of this positive output signal increases in accordance with the amount of rotation from the origin position.

  If the torque sensor of the fourteenth embodiment is in the negative torque range, in stage B, each permanent magnet piece 82A of the magnet ring arrangement 82 approaches the angular position θ2, moves away from the outer magnetic pole 14b, and the magnetic pole 82B moves to the outer magnetic pole 14b. Get closer. In stage C, each permanent magnet piece 83A of the magnet ring arrangement 83 approaches the angular position θ2, approaches the outer magnetic pole 14c, and the magnetic pole 83B moves away from the outer magnetic pole 14c. As a result, the detected magnetic flux DF1 flowing from each permanent magnet piece 82A of the magnet ring arrangement 82 to the magnetic sensor 15 decreases, the detected magnetic flux DF2 flowing from each permanent magnet piece 83A of the magnet ring arrangement 83 to the magnetic sensor 15 increases, and the magnetic The sensor 15 obtains a negative output signal, and the magnitude of the negative output signal increases in accordance with the amount of rotation from the origin position.

  As described above, according to the fourteenth embodiment, the bipolar stage output signal similar to that of the first embodiment can be obtained from the magnetic sensor 15 using the two stages B and C.

Embodiment 15 FIG.
43 to 53 show a torque sensor according to a fifteenth embodiment of the present invention. 43, 44, 45, 46, and 47 are views showing the torque sensor according to the fifteenth embodiment at its origin position. 48, 49, and 50 are diagrams showing the torque sensor according to the first embodiment in its positive torque range. 51, 52, and 53 show the fifteenth embodiment in its negative torque range. FIG. 43 is a top view of the torque sensor according to the fifteenth embodiment as viewed in the axial direction, but some of the components are omitted for easy viewing of the drawing. 44, 48, and 51 are longitudinal sectional views of the torque sensor according to the fifteenth embodiment cut along a plane including the common axis LL. 45 is a cross-sectional view taken along line BB in FIG. 44, FIG. 46 is a cross-sectional view taken along line CC in FIG. 44, and FIG. 47 is a cross-sectional view taken along line EE in FIG. Figure 49 is sectional view taken along line B-B of FIG. 48, FIG. 50 is a sectional view taken along line C-C of FIG 8. 52 is a sectional view taken along line BB in FIG. 51, and FIG. 53 is a sectional view taken along line CC in FIG. The BB line, CC line, and EE line are all included in a plane orthogonal to the common axis LL.

In the fifteenth embodiment, in the first embodiment, the outer peripheral rotating body 12 is constituted by one outer peripheral cylinder c, the stages A and D are deleted, a new stage E is provided, and a detection magnetic path 20 is provided in the stage E. And the magnetic sensor 15 are provided, and the other configuration is the same as that of the first embodiment.

In the fifteenth embodiment, the outer peripheral rotating body 12 is constituted by one outer peripheral cylinder 12c. The outer peripheral cylinder 12c is a cylinder arranged around the common axis LL, and is arranged so that its central axis coincides with the common axis LL. The outer peripheral cylinder 12 c is made of a magnetic material such as iron and is disposed on the outer periphery of the inner peripheral cylinder 3.

  In the fifteenth embodiment, the stages A and D of the first embodiment are deleted, and the same stages B and C as in the first embodiment and a new stage E are provided in addition thereto. As in the first embodiment, the stage B is provided with the surrounding magnet structure 6B constituting the magnetic field generating means 6 and the magnetic field changing means 32 including the inner peripheral magnetic pole 11b and the outer peripheral magnetic pole 14b. As in the first embodiment, the stage C is provided with the surrounding magnet structure 6C constituting the magnetic field generating means 6, and the magnetic field changing means 33 including the inner peripheral magnetic pole 11c and the outer peripheral magnetic pole 14c. As shown in FIGS. 45 and 46, the enclosing magnet structures 6B and 6C are similar to the first embodiment, respectively, in the ring-shaped permanent magnet 62 magnetized in the radial direction around the common axis LL. The ring-shaped permanent magnets 62 and 63 are magnetized in opposite directions. The outer peripheral magnetic poles 14b and 14c are disposed on the inner peripheral surface of the outer peripheral cylinder 12c.

  The stage E is formed corresponding to the upper end portion of the outer peripheral cylinder 12c. 47, the outer ring-shaped yoke 18a and the inner ring-shaped yoke 18b shown in FIG. 47 are arranged, and the detection magnetic path 20 and the magnetic sensor 15 are arranged between the ring-shaped yokes 18a and 18b. Is done. As shown in FIG. 44, the outer peripheral ring-shaped yoke 18a faces the upper end surface of the outer peripheral cylinder 12c via a minute gap. The inner peripheral ring-shaped yoke 18b faces the outer peripheral surface of the inner peripheral cylinder 3 through a minute gap. Although the inner cylinder 3 and the outer cylinder 12c are configured to be rotatable, the ring-shaped yokes 18a and 18b and the magnetic sensor 15 are fixed in an absolute space.

  As in the first embodiment, the ring-shaped permanent magnet 62 constituting the enclosing magnet structure 6B is worn so that only the S poles are arranged on the inner peripheral magnetic pole surface 62a and only the N poles are arranged on the outer peripheral magnetic pole surface 62b. Magnetized. However, the ring-shaped permanent magnet 63 constituting the surrounding magnet structure 6C is magnetized in the opposite direction to the ring-shaped permanent magnet 62, and only the N pole is provided on the inner peripheral magnetic pole face 63a, and the outer peripheral magnetic pole face 63b. Only the S pole is formed continuously.

  In the torque sensor of the fifteenth embodiment, as shown in FIG. 44, between the stages B and C, from the outer peripheral magnetic pole surface 62b of the ring-shaped permanent magnet 62, the inner peripheral magnetic pole 11b, the outer peripheral magnetic pole 14b, and the outer peripheral cylinder 12c. The magnetic flux Φ passing through the outer peripheral magnetic pole 14c, the inner peripheral magnetic pole 11c, the ring-shaped permanent magnet 63, and the inner peripheral cylinder 3 and returning to the ring-shaped permanent magnet 62 flows. Further, the detection magnetic path 20 including the magnetic sensor 15 flows through the detection magnetic flux DF1 due to the ring-shaped permanent magnet 62 and the detection magnetic flux DF2 due to the ring-shaped permanent magnet 63.

  The detection magnetic flux DF1 is transmitted from the outer peripheral magnetic pole surface 62b of the ring-shaped permanent magnet 62 to the inner peripheral magnetic pole 11b, the outer peripheral magnetic pole 14b, the outer peripheral cylinder 12c, the ring-shaped yoke 18a, the detection magnetic path 20, the magnetic sensor 15, the ring-shaped yoke 18b, It flows through a magnetic path that passes through the inner peripheral cylinder 3 and returns to the inner peripheral magnetic pole surface 62a. The detection magnetic flux DF2 is transmitted from the inner peripheral magnetic pole surface 63a of the ring-shaped permanent magnet 63 to the inner peripheral cylinder 3, the ring-shaped yoke 18b, the detection magnetic path 20, the magnetic sensor 15, the ring-shaped yoke 18a, the outer peripheral cylinder 12c, and the outer periphery. The magnetic flux passes through the magnetic pole 14c and the inner peripheral magnetic pole 11c, and flows to the magnetic path returning to the outer peripheral magnetic pole surface 63b of the ring-shaped permanent magnet 63. The detection magnetic fluxes DF1 and DF2 flow in opposite directions in the detection magnetic path 20.

In the state where the torque sensor is at the origin position, as shown in FIG. 43, each of the inner peripheral magnetic poles 11b and 11c has an angular position θ1 where the outer peripheral magnetic pole 14b is positioned and an angular position θ2 where the outer peripheral magnetic pole 14c is positioned. Located just in the middle. At this origin position, the magnetic resistance between the inner peripheral magnetic pole 11b and the outer peripheral magnetic pole 14b in the stage B is equal to the magnetic resistance between the inner peripheral magnetic pole 11c and the outer peripheral magnetic pole 14c in the stage C, so that the detected magnetic flux DF1, The magnitudes of DF2 are substantially equal to each other, and the detected magnetic flux DF, which is the sum of these detected magnetic fluxes DF1 and DF2, becomes zero. At this origin position, as a result, the detected magnetic flux DF flowing through the magnetic sensor 15 becomes zero, and only the magnetic flux Φ flows between the stages B and C as shown in FIG.

In the state where the torque sensor is in the positive torque range, in stage B, as shown in FIG. 49, the inner circumferential magnetic pole 11b moves away from the angular position θ2, approaches the angular position θ1, and the inner circumferential magnetic pole 11b approaches the outer magnetic pole 14b. On the other hand, in stage C, as shown in FIG. 50, the inner circumferential magnetic pole 11c moves away from the angular position θ2, approaches the angular position θ1, and the inner circumferential magnetic pole 11c becomes the outer circumferential magnetic pole 14c. The magnetic resistance between them increases away from them. As a result, the detection magnetic flux DF1 passing through the detection magnetic path 20 shown in FIG. 48 increases, and a positive output signal is obtained from the magnetic sensor 15.

  In the state where the torque sensor is in the negative torque range, in stage C, as shown in FIG. 52, the inner circumferential magnetic pole 11b is moved away from the angular position θ1, approached to the angular position θ2, and the inner circumferential magnetic pole 11b is moved away from the outer circumferential magnetic pole 14b. On the other hand, in the stage C, as shown in FIG. 53, the inner peripheral magnetic pole 11c moves away from the angular position θ1, approaches the angular position θ2, and the inner peripheral magnetic pole 11c becomes the outer magnetic pole 14c. Approaching, the magnetic resistance between them decreases. As a result, as shown in FIG. 51, the detected magnetic flux DF2 passing through the detected magnetic path 20 increases, and a negative output signal is obtained from the magnetic sensor 15.

  Thus, according to the fifteenth embodiment, the bipolar stage output signal similar to that of the first embodiment is obtained from the magnetic sensor 15 using the two stages B and C in which the magnetic field changing means 32 and 33 are arranged. Can do.

Also in the fifteenth embodiment, a ring-shaped yoke 18a, and 18b, and more and a magnetic sensor 15, etc. molding resin, can be integrated with each other. In the stage E, a ring-shaped iron core can be provided on the inner peripheral cylinder 3, and the ring-shaped yoke 18b can be opposed to the outer peripheral surface of the ring-shaped iron core via a minute gap. In the fifteenth embodiment, the surrounding magnet structures 6B and 6C can be changed to the structures of the third to eighth embodiments. In any case, in the surrounding magnet structures 6B and 6C, the magnetization direction is reversed.

  The torque sensor according to the present invention is used, for example, to detect a steering torque acting on a steering wheel of an automobile. However, any other application can be used as long as it detects torque.

The top view in the origin position of Embodiment 1 of the torque sensor by this invention. FIG. 3 is a longitudinal sectional view at the origin position in the first embodiment. FIG. 3 is an operation explanatory diagram at the origin position in the first embodiment. FIG. 3 is a top view in the positive torque range of the first embodiment. FIG. 3 is a longitudinal sectional view in the positive torque range of the first embodiment. Operation | movement explanatory drawing in the positive torque range of Embodiment 1. FIG. AA line sectional view of Drawing 5. BB sectional drawing of FIG. The CC sectional view taken on the line of FIG. The DD sectional view taken on the line of FIG. FIG. 3 is a side view of the first embodiment. The longitudinal cross-sectional view of Embodiment 2 of the torque sensor by this invention. The top view in the positive torque range of Embodiment 3 of the torque sensor by this invention. AA line sectional view of Drawing 13. FIG. 14 is a cross-sectional view taken along line BB and CC in FIG. 13. The DD sectional view taken on the line of FIG. The longitudinal cross-sectional view of Embodiment 4 of the torque sensor by this invention. FIG. 17 is a cross-sectional view taken along line B-B and CC. The longitudinal cross-sectional view in the positive torque range of Embodiment 5 of the torque sensor by this invention. AA line sectional view of Drawing 19.

BB sectional drawing of FIG. The CC sectional view taken on the line of FIG. The DD sectional view taken on the line of FIG. Sectional drawing in the stage B of Embodiment 6 of the torque sensor by this invention. Sectional drawing in the stage C of Embodiment 6. FIG. The top view of Embodiment 7 of the torque sensor by this invention. The top view of Embodiment 8 of the torque sensor by this invention. FIG. 10 is a longitudinal sectional view in the positive torque range of the eighth embodiment. AA line sectional view of Drawing 28. B-B shear plane view of FIG. 28. The CC sectional view taken on the line of FIG. The DD sectional view taken on the line of FIG. A top view of a torque sensor according to a ninth embodiment of the present invention. A top view of a torque sensor according to a tenth embodiment of the present invention. A top view of an eleventh embodiment of the torque sensor according to the present invention. The front view of Embodiment 12 of the torque sensor by this invention. FIG. 21 is a side view of the twelfth embodiment. A front view of a torque sensor according to a thirteenth embodiment of the present invention. The top view in the origin position of Embodiment 14 of the torque sensor by this invention. FIG. 25 is a longitudinal sectional view in the positive torque range of the fourteenth embodiment.

The BB sectional view taken on the line of FIG. The CC sectional view taken on the line of FIG. The top view in the origin position of Embodiment 15 of the torque sensor by this invention. FIG. 17 is a longitudinal sectional view at the origin position in a fifteenth embodiment. The BB sectional view taken on the line of FIG. C-C shear plane view of FIG. 44. The EE sectional view taken on the line of FIG. FIG. 25 is a longitudinal sectional view in the positive torque range of the fifteenth embodiment. The BB sectional view taken on the line of FIG. The CC sectional view taken on the line of FIG. FIG. 25 is a longitudinal sectional view in the negative torque range of the fifteenth embodiment. FIG. 52 is a sectional view taken along line BB in FIG. 51. The CC sectional view taken on the line of FIG.

1: first rotating shaft, 2: second rotating shaft, 3: inner periphery rotating body, 4: base plate,
5: Torsion bar
6: Magnetic field generating means, 6A, 6B, 6C, 6D: Enclosed magnet structure,
61, 62, 63, 64, 65, 66: ring-shaped permanent magnets,
67, 68: Ring-shaped magnet body,
69, 72, 73: Magnet ring arrangement,
69A, 72A, 73A, 82A, 83A: permanent magnet pieces,
61a, 62a, 63a, 64a, 65a, 66a, 67a, 68a, 69a, 72a, 73a, 82a, 83a: inner peripheral magnetic pole surface, 82B, 83B: magnetic pole,
61b, 62b, 63b, 64b, 65b, 66b, 67b, 68b, 69b, 72b, 73b, 82b, 83b: outer peripheral magnetic pole surface, 7, 8, 9, 10: ring-shaped iron core,
7a, 8b: magnetic surface,
11a, 11b, 11c, 11d: inner peripheral magnetic pole, 12: outer peripheral rotating body,
12a, 12b, 12c: outer peripheral cylinder, 13, 13a: connecting body,
14a, 14b, 14c, 14d: outer peripheral magnetic pole, 15: magnetic sensor,
18a, 18b: ring-shaped yoke, 20: detection magnetic path, DF1, DF2: detection magnetic flux,
30, 31, 32, 33, 34: magnetic field changing means, 32A, 33A: magnetic field forming means,
LL: common axis, AA: stage A, BB: stage B, CC: stage C,
DD: Stage D, EE: E stage.

Claims (9)

A first rotating shaft and a second rotating shaft are disposed on a common axis, and the first rotating shaft and the second rotating shaft are coupled by a torsion bar, and between the first rotating shaft and the second rotating shaft. A torque sensor for detecting a torsion torque to be applied;
An inner peripheral rotating body connected to the first rotating shaft, an outer peripheral rotating body connected to the second rotating shaft and surrounding the inner rotating body, and the inner peripheral rotating body and the outer peripheral rotating body. Magnetic field generating means, a magnetic sensor through which the detected magnetic flux flows from the magnetic field generating means through the inner peripheral rotating body and the outer peripheral rotating body, and relative rotation between the first rotating shaft and the second rotating shaft in a positive torque range. Accordingly, the first magnetic field changing means for causing the detected magnetic flux to flow through the magnetic sensor in a predetermined direction and changing the magnitude thereof, and the relative rotation between the first rotating shaft and the second rotating shaft in a negative torque range, Second magnetic field changing means for causing a detected magnetic flux to flow through the magnetic sensor in a direction opposite to the predetermined direction and changing the magnitude thereof;
The magnetic sensor is configured to generate an output signal whose polarity changes according to the direction of the detected magnetic flux and whose magnitude changes according to the magnitude of the detected magnetic flux, and the magnetic field generating means includes: Including at least one enclosing magnet structure arranged to surround the common axis, the enclosing magnet structure having an outer peripheral magnetic pole surface and an inner peripheral magnetic pole surface around the common axis;
The enclosing magnet structure is composed of a ring-shaped permanent magnet disposed around the common axis, and the outer peripheral magnetic pole surface is formed between the N-pole and S-pole magnetic poles along the circumference of the common axis. only poles of one polarity are continuously formed in, also in said peripheral pole faces, along the circumference of the common axis, only the other magnetic pole of polarity in said magnetic poles are formed continuously Torque sensor characterized by the above. 2. The torque sensor according to claim 1 , wherein an outer peripheral magnetic pole of the magnetic field changing means is arranged to face an outer peripheral magnetic pole surface of the enclosing magnet structure with a gap, and the outer peripheral magnetic pole surface of the enclosing magnet structure is the air gap. Torque sensor characterized by being exposed to A torque sensor according to claim 1, wherein, before Kigaishu pole faces, only one pole polarity in said magnetic poles is projected at a predetermined angular intervals along the circumference of the common axis, also Only the magnetic pole of the other polarity of the two magnetic poles is continuously formed on the inner peripheral magnetic pole surface along the common axis. A first rotating shaft and a second rotating shaft are disposed on a common axis, and the first rotating shaft and the second rotating shaft are coupled by a torsion bar, and between the first rotating shaft and the second rotating shaft. A torque sensor for detecting a torsion torque to be applied;
An inner peripheral rotating body connected to the first rotating shaft, an outer peripheral rotating body connected to the second rotating shaft and surrounding the inner rotating body, and the inner peripheral rotating body and the outer peripheral rotating body. Magnetic field generating means, a magnetic sensor through which the detected magnetic flux flows from the magnetic field generating means through the inner peripheral rotating body and the outer peripheral rotating body, and relative rotation between the first rotating shaft and the second rotating shaft in a positive torque range. Accordingly, the first magnetic field changing means for causing the detected magnetic flux to flow through the magnetic sensor in a predetermined direction and changing the magnitude thereof, and the relative rotation between the first rotating shaft and the second rotating shaft in a negative torque range, Second magnetic field changing means for causing a detected magnetic flux to flow through the magnetic sensor in a direction opposite to the predetermined direction and changing the magnitude thereof;
The magnetic sensor is configured to generate an output signal whose polarity changes according to the direction of the detected magnetic flux and whose magnitude changes according to the magnitude of the detected magnetic flux;
The magnetic field generating means includes at least one enclosing magnet structure disposed so as to surround the common axis, and the enclosing magnet structure has an outer peripheral magnetic pole surface and an inner peripheral magnetic pole surface around the common axis,
The surrounding magnet structure is composed of a ring-shaped magnet body arranged around the common axis, and this ring-shaped magnet body has only one magnetic pole of the two magnetic poles on the outer peripheral magnetic pole surface. Arranged at a predetermined angular interval around the common axis, and only the magnetic pole of the other polarity of the two magnetic poles is arranged at a predetermined angular interval around the common axis on the inner peripheral magnetic pole surface. A torque sensor characterized by being magnetized in a line. A torque sensor according to claim 1 or 4, wherein said common axis at least the first along the second stage is provided, the first magnetic field changing means is the first stage and said second magnetic field varying means Are arranged on the second stage, respectively. 6. The torque sensor according to claim 5 , wherein the magnetic field generating means includes at least first and second surrounding magnet structures, and the first surrounding magnet structure is disposed on the first stage, and the second stage. A torque sensor characterized in that a surrounding magnet structure is arranged on the second stage. 6. The torque sensor according to claim 5 , wherein third and fourth stages are further provided along the common axis, and the third stage, together with the first magnetic field changing means, in the positive torque range. Third magnetic field changing means for causing the detected magnetic flux to flow in a predetermined direction and changing its magnitude in accordance with relative rotation between the first rotating shaft and the second rotating shaft is disposed, and the second stage includes the second magnetic field changing means. Together with the magnetic field changing means, fourth magnetic field changing means for causing the detected magnetic flux to flow in a direction opposite to the predetermined direction in accordance with the relative rotation of the first rotating shaft and the second rotating shaft in a negative torque range and changing the magnitude thereof. A torque sensor characterized in that is arranged. A torque sensor according to claim 1 or 4, wherein the outer peripheral rotating body, wherein a common axis first peripheral case arranged along the second peripheral case, and these first peripheral case the A torque sensor, wherein the detection magnetic path is formed between two outer cylinders. A torque sensor according to claim 1 or 4, wherein the outer peripheral rotary body has a single peripheral case, between the outer peripheral surface of the inner peripheral rotor and end of the peripheral case, the detection magnetic A torque sensor characterized in that a path is formed.

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